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ff6686d2 | 1 | /* Interprocedural scalar replacement of aggregates |
c76b3bc5 | 2 | Copyright (C) 2019-2022 Free Software Foundation, Inc. |
ff6686d2 MJ |
3 | Contributed by Martin Jambor <mjambor@suse.cz> |
4 | ||
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it under | |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 3, or (at your option) any later | |
10 | version. | |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
13 | 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 GCC; see the file COPYING3. If not see | |
19 | <http://www.gnu.org/licenses/>. */ | |
20 | ||
21 | /* IPA-SRA is an interprocedural pass that removes unused function return | |
22 | values (turning functions returning a value which is never used into void | |
c76b3bc5 | 23 | functions) and removes unused function parameters. It can also replace an |
ff6686d2 MJ |
24 | aggregate parameter by a set of other parameters representing part of the |
25 | original, turning those passed by reference into new ones which pass the | |
26 | value directly. | |
27 | ||
28 | The pass is a true IPA one, which means that it works in three stages in | |
29 | order to be able to take advantage of LTO. First, summaries about functions | |
30 | and each calls are generated. Function summaries (often called call graph | |
31 | node summaries) contain mainly information about which parameters are | |
32 | potential transformation candidates and which bits of candidates are | |
33 | accessed. We differentiate between accesses done as a part of a call | |
34 | statement (which might be not necessary if the callee is also transformed) | |
35 | and others (which are mandatory). Call summaries (often called call graph | |
36 | edge summaries) contain information about which function formal parameters | |
37 | feed into which actual call arguments so that if two parameters are only | |
38 | used in a sum which is then passed to another function which then however | |
39 | does not use this parameter, all three parameters of the two functions can | |
40 | be eliminated. Edge summaries also have flags whether the return value is | |
41 | used or if it is only returned in the caller too. In LTO mode these | |
42 | summaries are then streamed to the object file in the compilation phase and | |
43 | streamed back in in the WPA analysis stage. | |
44 | ||
45 | The interprocedural analysis phase traverses the graph in topological order | |
46 | in two sweeps, one in each direction. First, from callees to callers for | |
47 | parameter removal and splitting. Each strongly-connected component is | |
48 | processed iteratively until the situation in it stabilizes. The pass from | |
49 | callers to callees is then carried out to remove unused return values in a | |
50 | very similar fashion. | |
51 | ||
52 | Because parameter manipulation has big implications for call redirection | |
53 | which is done only after all call graph nodes materialize, the | |
54 | transformation phase is not part of this patch but is carried out by the | |
55 | clone materialization and edge redirection itself, see comments in | |
56 | ipa-param-manipulation.h for more details. */ | |
57 | ||
58 | ||
ff6686d2 MJ |
59 | #include "config.h" |
60 | #include "system.h" | |
61 | #include "coretypes.h" | |
62 | #include "backend.h" | |
63 | #include "tree.h" | |
64 | #include "gimple.h" | |
65 | #include "predict.h" | |
66 | #include "tree-pass.h" | |
67 | #include "ssa.h" | |
68 | #include "cgraph.h" | |
69 | #include "gimple-pretty-print.h" | |
70 | #include "alias.h" | |
71 | #include "tree-eh.h" | |
72 | #include "gimple-iterator.h" | |
73 | #include "gimple-walk.h" | |
74 | #include "tree-dfa.h" | |
75 | #include "tree-sra.h" | |
a895e6d7 | 76 | #include "alloc-pool.h" |
ff6686d2 | 77 | #include "symbol-summary.h" |
ff6686d2 MJ |
78 | #include "dbgcnt.h" |
79 | #include "tree-inline.h" | |
80 | #include "ipa-utils.h" | |
81 | #include "builtins.h" | |
82 | #include "cfganal.h" | |
83 | #include "tree-streamer.h" | |
9707b593 | 84 | #include "internal-fn.h" |
ae7a23a3 | 85 | #include "symtab-clones.h" |
ecdf414b | 86 | #include "attribs.h" |
4834e936 | 87 | #include "ipa-prop.h" |
ff6686d2 | 88 | |
40e67ab8 JH |
89 | static void ipa_sra_summarize_function (cgraph_node *); |
90 | ||
ff6686d2 MJ |
91 | /* Bits used to track size of an aggregate in bytes interprocedurally. */ |
92 | #define ISRA_ARG_SIZE_LIMIT_BITS 16 | |
93 | #define ISRA_ARG_SIZE_LIMIT (1 << ISRA_ARG_SIZE_LIMIT_BITS) | |
94 | /* How many parameters can feed into a call actual argument and still be | |
c76b3bc5 | 95 | tracked. */ |
ff6686d2 MJ |
96 | #define IPA_SRA_MAX_PARAM_FLOW_LEN 7 |
97 | ||
98 | /* Structure describing accesses to a specific portion of an aggregate | |
99 | parameter, as given by the offset and size. Any smaller accesses that occur | |
100 | within a function that fall within another access form a tree. The pass | |
101 | cannot analyze parameters with only partially overlapping accesses. */ | |
102 | ||
103 | struct GTY(()) param_access | |
104 | { | |
105 | /* Type that a potential replacement should have. This field only has | |
106 | meaning in the summary building and transformation phases, when it is | |
dfea3d6f | 107 | reconstructed from the body. Must not be touched in IPA analysis |
ff6686d2 MJ |
108 | stage. */ |
109 | tree type; | |
110 | ||
111 | /* Alias reference type to be used in MEM_REFs when adjusting caller | |
112 | arguments. */ | |
113 | tree alias_ptr_type; | |
114 | ||
115 | /* Values returned by get_ref_base_and_extent but converted to bytes and | |
116 | stored as unsigned ints. */ | |
117 | unsigned unit_offset; | |
118 | unsigned unit_size : ISRA_ARG_SIZE_LIMIT_BITS; | |
119 | ||
120 | /* Set once we are sure that the access will really end up in a potentially | |
121 | transformed function - initially not set for portions of formal parameters | |
122 | that are only used as actual function arguments passed to callees. */ | |
123 | unsigned certain : 1; | |
c76b3bc5 | 124 | /* Set if the access has reverse scalar storage order. */ |
ff6686d2 MJ |
125 | unsigned reverse : 1; |
126 | }; | |
127 | ||
dfea3d6f | 128 | /* This structure has the same purpose as the one above and additionally it |
ff6686d2 MJ |
129 | contains some fields that are only necessary in the summary generation |
130 | phase. */ | |
131 | ||
132 | struct gensum_param_access | |
133 | { | |
134 | /* Values returned by get_ref_base_and_extent. */ | |
135 | HOST_WIDE_INT offset; | |
136 | HOST_WIDE_INT size; | |
137 | ||
138 | /* if this access has any children (in terms of the definition above), this | |
139 | points to the first one. */ | |
140 | struct gensum_param_access *first_child; | |
141 | /* In intraprocedural SRA, pointer to the next sibling in the access tree as | |
142 | described above. */ | |
143 | struct gensum_param_access *next_sibling; | |
144 | ||
145 | /* Type that a potential replacement should have. This field only has | |
146 | meaning in the summary building and transformation phases, when it is | |
dfea3d6f | 147 | reconstructed from the body. Must not be touched in IPA analysis |
ff6686d2 MJ |
148 | stage. */ |
149 | tree type; | |
dfea3d6f | 150 | /* Alias reference type to be used in MEM_REFs when adjusting caller |
ff6686d2 MJ |
151 | arguments. */ |
152 | tree alias_ptr_type; | |
153 | ||
10478270 MJ |
154 | /* Cumulative count of all loads. */ |
155 | profile_count load_count; | |
ff6686d2 MJ |
156 | /* Have there been writes to or reads from this exact location except for as |
157 | arguments to a function call that can be tracked. */ | |
158 | bool nonarg; | |
159 | ||
c76b3bc5 | 160 | /* Set if the access has reverse scalar storage order. */ |
ff6686d2 MJ |
161 | bool reverse; |
162 | }; | |
163 | ||
164 | /* Summary describing a parameter in the IPA stages. */ | |
165 | ||
166 | struct GTY(()) isra_param_desc | |
167 | { | |
168 | /* List of access representatives to the parameters, sorted according to | |
169 | their offset. */ | |
170 | vec <param_access *, va_gc> *accesses; | |
171 | ||
172 | /* Unit size limit of total size of all replacements. */ | |
173 | unsigned param_size_limit : ISRA_ARG_SIZE_LIMIT_BITS; | |
174 | /* Sum of unit sizes of all certain replacements. */ | |
175 | unsigned size_reached : ISRA_ARG_SIZE_LIMIT_BITS; | |
f2cf4c61 MJ |
176 | /* Minimum offset that is known to be safe to dereference because of callers |
177 | pass pointers to DECLs of at least this size or because of dereferences in | |
178 | callers. */ | |
179 | unsigned safe_size : ISRA_ARG_SIZE_LIMIT_BITS; | |
ff6686d2 MJ |
180 | |
181 | /* A parameter that is used only in call arguments and can be removed if all | |
182 | concerned actual arguments are removed. */ | |
183 | unsigned locally_unused : 1; | |
184 | /* An aggregate that is a candidate for breaking up or complete removal. */ | |
185 | unsigned split_candidate : 1; | |
186 | /* Is this a parameter passing stuff by reference? */ | |
187 | unsigned by_ref : 1; | |
e3a5cc32 MJ |
188 | /* Parameter hint set during IPA analysis when there is a caller which does |
189 | not construct the argument just to pass it to calls. Only meaningful for | |
190 | by_ref parameters. */ | |
191 | unsigned not_specially_constructed : 1; | |
f2cf4c61 MJ |
192 | /* Only meaningful for by_ref parameters. If set, this parameter can only be |
193 | a split candidate if all callers pass pointers that are known to point to | |
194 | a chunk of memory large enough to contain all accesses. */ | |
195 | unsigned conditionally_dereferenceable : 1; | |
196 | /* Set when safe_size has been updated from at least one caller. */ | |
197 | unsigned safe_size_set : 1; | |
ff6686d2 MJ |
198 | }; |
199 | ||
200 | /* Structure used when generating summaries that describes a parameter. */ | |
201 | ||
202 | struct gensum_param_desc | |
203 | { | |
204 | /* Roots of param_accesses. */ | |
205 | gensum_param_access *accesses; | |
206 | /* Number of accesses in the access tree rooted in field accesses. */ | |
207 | unsigned access_count; | |
208 | ||
dfea3d6f | 209 | /* If the below is non-zero, this is the number of uses as actual arguments. */ |
ff6686d2 MJ |
210 | int call_uses; |
211 | /* Number of times this parameter has been directly passed to. */ | |
212 | unsigned ptr_pt_count; | |
213 | ||
214 | /* Size limit of total size of all replacements. */ | |
215 | unsigned param_size_limit; | |
216 | /* Sum of sizes of nonarg accesses. */ | |
217 | unsigned nonarg_acc_size; | |
218 | ||
219 | /* A parameter that is used only in call arguments and can be removed if all | |
220 | concerned actual arguments are removed. */ | |
221 | bool locally_unused; | |
222 | /* An aggregate that is a candidate for breaking up or a pointer passing data | |
223 | by reference that is a candidate for being converted to a set of | |
dfea3d6f | 224 | parameters passing those data by value. */ |
ff6686d2 | 225 | bool split_candidate; |
10478270 MJ |
226 | /* Is this a parameter passing stuff by reference (either a pointer or a |
227 | source language reference type)? */ | |
ff6686d2 | 228 | bool by_ref; |
10478270 MJ |
229 | /* If this parameter passes stuff by reference, can it be safely dereferenced |
230 | without performing further checks (for example because it is a | |
231 | REFERENCE_TYPE)? */ | |
232 | bool safe_ref; | |
f2cf4c61 MJ |
233 | /* Only meaningful for by_ref parameters. If set, this parameter can only be |
234 | a split candidate if all callers pass pointers that are known to point to | |
235 | a chunk of memory large enough to contain all accesses. */ | |
236 | bool conditionally_dereferenceable; | |
ff6686d2 MJ |
237 | |
238 | /* The number of this parameter as they are ordered in function decl. */ | |
239 | int param_number; | |
240 | /* For parameters passing data by reference, this is parameter index to | |
241 | compute indices to bb_dereferences. */ | |
242 | int deref_index; | |
243 | }; | |
244 | ||
dfea3d6f | 245 | /* Properly deallocate accesses of DESC. TODO: Since this data structure is |
c76b3bc5 EB |
246 | allocated in GC memory, this is not necessary and we can consider removing |
247 | the function. */ | |
ff6686d2 MJ |
248 | |
249 | static void | |
250 | free_param_decl_accesses (isra_param_desc *desc) | |
251 | { | |
252 | unsigned len = vec_safe_length (desc->accesses); | |
253 | for (unsigned i = 0; i < len; ++i) | |
254 | ggc_free ((*desc->accesses)[i]); | |
255 | vec_free (desc->accesses); | |
256 | } | |
257 | ||
258 | /* Class used to convey information about functions from the | |
dfea3d6f | 259 | intra-procedural analysis stage to inter-procedural one. */ |
ff6686d2 MJ |
260 | |
261 | class GTY((for_user)) isra_func_summary | |
262 | { | |
263 | public: | |
264 | /* initialize the object. */ | |
265 | ||
266 | isra_func_summary () | |
267 | : m_parameters (NULL), m_candidate (false), m_returns_value (false), | |
268 | m_return_ignored (false), m_queued (false) | |
269 | {} | |
270 | ||
271 | /* Destroy m_parameters. */ | |
272 | ||
273 | ~isra_func_summary (); | |
274 | ||
dfea3d6f | 275 | /* Mark the function as not a candidate for any IPA-SRA transformation. |
ff6686d2 MJ |
276 | Return true if it was a candidate until now. */ |
277 | ||
278 | bool zap (); | |
279 | ||
280 | /* Vector of parameter descriptors corresponding to the function being | |
281 | analyzed. */ | |
282 | vec<isra_param_desc, va_gc> *m_parameters; | |
283 | ||
284 | /* Whether the node is even a candidate for any IPA-SRA transformation at | |
285 | all. */ | |
286 | unsigned m_candidate : 1; | |
287 | ||
288 | /* Whether the original function returns any value. */ | |
289 | unsigned m_returns_value : 1; | |
290 | ||
291 | /* Set to true if all call statements do not actually use the returned | |
292 | value. */ | |
293 | ||
294 | unsigned m_return_ignored : 1; | |
295 | ||
296 | /* Whether the node is already queued in IPA SRA stack during processing of | |
297 | call graphs SCCs. */ | |
298 | ||
299 | unsigned m_queued : 1; | |
300 | }; | |
301 | ||
c76b3bc5 EB |
302 | /* Deallocate the memory pointed to by isra_func_summary. TODO: Since this |
303 | data structure is allocated in GC memory, this is not necessary and we can | |
304 | consider removing the destructor. */ | |
ff6686d2 MJ |
305 | |
306 | isra_func_summary::~isra_func_summary () | |
307 | { | |
308 | unsigned len = vec_safe_length (m_parameters); | |
309 | for (unsigned i = 0; i < len; ++i) | |
310 | free_param_decl_accesses (&(*m_parameters)[i]); | |
311 | vec_free (m_parameters); | |
312 | } | |
313 | ||
dfea3d6f | 314 | /* Mark the function as not a candidate for any IPA-SRA transformation. Return |
ff6686d2 MJ |
315 | true if it was a candidate until now. */ |
316 | ||
317 | bool | |
318 | isra_func_summary::zap () | |
319 | { | |
320 | bool ret = m_candidate; | |
321 | m_candidate = false; | |
322 | ||
c76b3bc5 | 323 | /* TODO: see the destructor above. */ |
ff6686d2 MJ |
324 | unsigned len = vec_safe_length (m_parameters); |
325 | for (unsigned i = 0; i < len; ++i) | |
326 | free_param_decl_accesses (&(*m_parameters)[i]); | |
327 | vec_free (m_parameters); | |
328 | ||
329 | return ret; | |
330 | } | |
331 | ||
332 | /* Structure to describe which formal parameters feed into a particular actual | |
c76b3bc5 | 333 | argument. */ |
ff6686d2 MJ |
334 | |
335 | struct isra_param_flow | |
336 | { | |
337 | /* Number of elements in array inputs that contain valid data. */ | |
338 | char length; | |
339 | /* Indices of formal parameters that feed into the described actual argument. | |
340 | If aggregate_pass_through or pointer_pass_through below are true, it must | |
341 | contain exactly one element which is passed through from a formal | |
342 | parameter if the given number. Otherwise, the array contains indices of | |
dfea3d6f | 343 | callee's formal parameters which are used to calculate value of this |
ff6686d2 MJ |
344 | actual argument. */ |
345 | unsigned char inputs[IPA_SRA_MAX_PARAM_FLOW_LEN]; | |
346 | ||
347 | /* Offset within the formal parameter. */ | |
348 | unsigned unit_offset; | |
f2cf4c61 MJ |
349 | /* When aggregate_pass_through is set, this is the size of the portion of an |
350 | aggregate formal parameter that is being passed. Otherwise, this is size | |
351 | of pointed to memory that is known to be valid be dereferenced. */ | |
ff6686d2 MJ |
352 | unsigned unit_size : ISRA_ARG_SIZE_LIMIT_BITS; |
353 | ||
f2cf4c61 | 354 | /* True when the value of this actual argument is a portion of a formal |
ff6686d2 MJ |
355 | parameter. */ |
356 | unsigned aggregate_pass_through : 1; | |
357 | /* True when the value of this actual copy is a verbatim pass through of an | |
358 | obtained pointer. */ | |
359 | unsigned pointer_pass_through : 1; | |
360 | /* True when it is safe to copy access candidates here from the callee, which | |
361 | would mean introducing dereferences into callers of the caller. */ | |
362 | unsigned safe_to_import_accesses : 1; | |
e3a5cc32 MJ |
363 | /* True when the passed value is an address of a structure that has been |
364 | constructed in the caller just to be passed by reference to functions | |
365 | (i.e. is never read). */ | |
366 | unsigned constructed_for_calls : 1; | |
ff6686d2 MJ |
367 | }; |
368 | ||
dfea3d6f | 369 | /* Structure used to convey information about calls from the intra-procedural |
ff6686d2 MJ |
370 | analysis stage to inter-procedural one. */ |
371 | ||
372 | class isra_call_summary | |
373 | { | |
374 | public: | |
375 | isra_call_summary () | |
376 | : m_arg_flow (), m_return_ignored (false), m_return_returned (false), | |
763121cc | 377 | m_bit_aligned_arg (false), m_before_any_store (false) |
ff6686d2 MJ |
378 | {} |
379 | ||
380 | void init_inputs (unsigned arg_count); | |
381 | void dump (FILE *f); | |
382 | ||
383 | /* Information about what formal parameters of the caller are used to compute | |
dfea3d6f | 384 | individual actual arguments of this call. */ |
ff6686d2 MJ |
385 | auto_vec <isra_param_flow> m_arg_flow; |
386 | ||
387 | /* Set to true if the call statement does not have a LHS. */ | |
388 | unsigned m_return_ignored : 1; | |
389 | ||
390 | /* Set to true if the LHS of call statement is only used to construct the | |
391 | return value of the caller. */ | |
392 | unsigned m_return_returned : 1; | |
393 | ||
394 | /* Set when any of the call arguments are not byte-aligned. */ | |
395 | unsigned m_bit_aligned_arg : 1; | |
763121cc MJ |
396 | |
397 | /* Set to true if the call happend before any (other) store to memory in the | |
398 | caller. */ | |
399 | unsigned m_before_any_store : 1; | |
ff6686d2 MJ |
400 | }; |
401 | ||
402 | /* Class to manage function summaries. */ | |
403 | ||
404 | class GTY((user)) ipa_sra_function_summaries | |
405 | : public function_summary <isra_func_summary *> | |
406 | { | |
407 | public: | |
408 | ipa_sra_function_summaries (symbol_table *table, bool ggc): | |
409 | function_summary<isra_func_summary *> (table, ggc) { } | |
410 | ||
f31ba116 DM |
411 | void duplicate (cgraph_node *, cgraph_node *, |
412 | isra_func_summary *old_sum, | |
413 | isra_func_summary *new_sum) final override; | |
414 | void insert (cgraph_node *, isra_func_summary *) final override; | |
ff6686d2 MJ |
415 | }; |
416 | ||
417 | /* Hook that is called by summary when a node is duplicated. */ | |
418 | ||
419 | void | |
420 | ipa_sra_function_summaries::duplicate (cgraph_node *, cgraph_node *, | |
421 | isra_func_summary *old_sum, | |
422 | isra_func_summary *new_sum) | |
423 | { | |
424 | /* TODO: Somehow stop copying when ISRA is doing the cloning, it is | |
425 | useless. */ | |
426 | new_sum->m_candidate = old_sum->m_candidate; | |
427 | new_sum->m_returns_value = old_sum->m_returns_value; | |
428 | new_sum->m_return_ignored = old_sum->m_return_ignored; | |
429 | gcc_assert (!old_sum->m_queued); | |
430 | new_sum->m_queued = false; | |
431 | ||
432 | unsigned param_count = vec_safe_length (old_sum->m_parameters); | |
433 | if (!param_count) | |
434 | return; | |
435 | vec_safe_reserve_exact (new_sum->m_parameters, param_count); | |
436 | new_sum->m_parameters->quick_grow_cleared (param_count); | |
437 | for (unsigned i = 0; i < param_count; i++) | |
438 | { | |
439 | isra_param_desc *s = &(*old_sum->m_parameters)[i]; | |
440 | isra_param_desc *d = &(*new_sum->m_parameters)[i]; | |
441 | ||
442 | d->param_size_limit = s->param_size_limit; | |
443 | d->size_reached = s->size_reached; | |
f2cf4c61 | 444 | d->safe_size = s->safe_size; |
ff6686d2 MJ |
445 | d->locally_unused = s->locally_unused; |
446 | d->split_candidate = s->split_candidate; | |
447 | d->by_ref = s->by_ref; | |
e3a5cc32 | 448 | d->not_specially_constructed = s->not_specially_constructed; |
f2cf4c61 MJ |
449 | d->conditionally_dereferenceable = s->conditionally_dereferenceable; |
450 | d->safe_size_set = s->safe_size_set; | |
ff6686d2 MJ |
451 | |
452 | unsigned acc_count = vec_safe_length (s->accesses); | |
453 | vec_safe_reserve_exact (d->accesses, acc_count); | |
454 | for (unsigned j = 0; j < acc_count; j++) | |
455 | { | |
456 | param_access *from = (*s->accesses)[j]; | |
457 | param_access *to = ggc_cleared_alloc<param_access> (); | |
458 | to->type = from->type; | |
459 | to->alias_ptr_type = from->alias_ptr_type; | |
460 | to->unit_offset = from->unit_offset; | |
461 | to->unit_size = from->unit_size; | |
462 | to->certain = from->certain; | |
c76b3bc5 | 463 | to->reverse = from->reverse; |
ff6686d2 MJ |
464 | d->accesses->quick_push (to); |
465 | } | |
466 | } | |
467 | } | |
468 | ||
469 | /* Pointer to the pass function summary holder. */ | |
470 | ||
471 | static GTY(()) ipa_sra_function_summaries *func_sums; | |
472 | ||
40e67ab8 JH |
473 | /* Hook that is called by summary when new node appears. */ |
474 | ||
475 | void | |
476 | ipa_sra_function_summaries::insert (cgraph_node *node, isra_func_summary *) | |
477 | { | |
478 | if (opt_for_fn (node->decl, flag_ipa_sra)) | |
479 | { | |
480 | push_cfun (DECL_STRUCT_FUNCTION (node->decl)); | |
481 | ipa_sra_summarize_function (node); | |
482 | pop_cfun (); | |
483 | } | |
484 | else | |
485 | func_sums->remove (node); | |
486 | } | |
487 | ||
ff6686d2 MJ |
488 | /* Class to manage call summaries. */ |
489 | ||
490 | class ipa_sra_call_summaries: public call_summary <isra_call_summary *> | |
491 | { | |
492 | public: | |
493 | ipa_sra_call_summaries (symbol_table *table): | |
494 | call_summary<isra_call_summary *> (table) { } | |
495 | ||
496 | /* Duplicate info when an edge is cloned. */ | |
f31ba116 DM |
497 | void duplicate (cgraph_edge *, cgraph_edge *, |
498 | isra_call_summary *old_sum, | |
499 | isra_call_summary *new_sum) final override; | |
ff6686d2 MJ |
500 | }; |
501 | ||
502 | static ipa_sra_call_summaries *call_sums; | |
503 | ||
504 | ||
505 | /* Initialize m_arg_flow of a particular instance of isra_call_summary. | |
506 | ARG_COUNT is the number of actual arguments passed. */ | |
507 | ||
508 | void | |
509 | isra_call_summary::init_inputs (unsigned arg_count) | |
510 | { | |
511 | if (arg_count == 0) | |
512 | { | |
513 | gcc_checking_assert (m_arg_flow.length () == 0); | |
514 | return; | |
515 | } | |
516 | if (m_arg_flow.length () == 0) | |
517 | { | |
518 | m_arg_flow.reserve_exact (arg_count); | |
519 | m_arg_flow.quick_grow_cleared (arg_count); | |
520 | } | |
521 | else | |
522 | gcc_checking_assert (arg_count == m_arg_flow.length ()); | |
523 | } | |
524 | ||
525 | /* Dump all information in call summary to F. */ | |
526 | ||
527 | void | |
528 | isra_call_summary::dump (FILE *f) | |
529 | { | |
530 | if (m_return_ignored) | |
531 | fprintf (f, " return value ignored\n"); | |
532 | if (m_return_returned) | |
533 | fprintf (f, " return value used only to compute caller return value\n"); | |
763121cc MJ |
534 | if (m_before_any_store) |
535 | fprintf (f, " happens before any store to memory\n"); | |
ff6686d2 MJ |
536 | for (unsigned i = 0; i < m_arg_flow.length (); i++) |
537 | { | |
538 | fprintf (f, " Parameter %u:\n", i); | |
539 | isra_param_flow *ipf = &m_arg_flow[i]; | |
540 | ||
541 | if (ipf->length) | |
542 | { | |
543 | bool first = true; | |
544 | fprintf (f, " Scalar param sources: "); | |
545 | for (int j = 0; j < ipf->length; j++) | |
546 | { | |
547 | if (!first) | |
548 | fprintf (f, ", "); | |
549 | else | |
550 | first = false; | |
551 | fprintf (f, "%i", (int) ipf->inputs[j]); | |
552 | } | |
553 | fprintf (f, "\n"); | |
554 | } | |
555 | if (ipf->aggregate_pass_through) | |
556 | fprintf (f, " Aggregate pass through from the param given above, " | |
557 | "unit offset: %u , unit size: %u\n", | |
558 | ipf->unit_offset, ipf->unit_size); | |
f2cf4c61 MJ |
559 | else if (ipf->unit_size > 0) |
560 | fprintf (f, " Known dereferenceable size: %u\n", ipf->unit_size); | |
ff6686d2 MJ |
561 | if (ipf->pointer_pass_through) |
562 | fprintf (f, " Pointer pass through from the param given above, " | |
563 | "safe_to_import_accesses: %u\n", ipf->safe_to_import_accesses); | |
e3a5cc32 MJ |
564 | if (ipf->constructed_for_calls) |
565 | fprintf (f, " Variable constructed just to be passed to " | |
566 | "calls.\n"); | |
ff6686d2 MJ |
567 | } |
568 | } | |
569 | ||
dfea3d6f | 570 | /* Duplicate edge summary when an edge is cloned. */ |
ff6686d2 MJ |
571 | |
572 | void | |
573 | ipa_sra_call_summaries::duplicate (cgraph_edge *, cgraph_edge *, | |
574 | isra_call_summary *old_sum, | |
575 | isra_call_summary *new_sum) | |
576 | { | |
577 | unsigned arg_count = old_sum->m_arg_flow.length (); | |
578 | new_sum->init_inputs (arg_count); | |
579 | for (unsigned i = 0; i < arg_count; i++) | |
580 | new_sum->m_arg_flow[i] = old_sum->m_arg_flow[i]; | |
581 | ||
582 | new_sum->m_return_ignored = old_sum->m_return_ignored; | |
583 | new_sum->m_return_returned = old_sum->m_return_returned; | |
584 | new_sum->m_bit_aligned_arg = old_sum->m_bit_aligned_arg; | |
763121cc | 585 | new_sum->m_before_any_store = old_sum->m_before_any_store; |
ff6686d2 MJ |
586 | } |
587 | ||
588 | ||
589 | /* With all GTY stuff done, we can move to anonymous namespace. */ | |
590 | namespace { | |
591 | /* Quick mapping from a decl to its param descriptor. */ | |
592 | ||
593 | hash_map<tree, gensum_param_desc *> *decl2desc; | |
594 | ||
6539bbc1 MJ |
595 | /* All local DECLs ever loaded from of and of those that have their address |
596 | assigned to a variable. */ | |
e3a5cc32 MJ |
597 | |
598 | hash_set <tree> *loaded_decls; | |
599 | ||
c76b3bc5 | 600 | /* Countdown of allowed Alias Analysis steps during summary building. */ |
ff6686d2 MJ |
601 | |
602 | int aa_walking_limit; | |
603 | ||
604 | /* This is a table in which for each basic block and parameter there is a | |
605 | distance (offset + size) in that parameter which is dereferenced and | |
606 | accessed in that BB. */ | |
607 | HOST_WIDE_INT *bb_dereferences = NULL; | |
608 | /* How many by-reference parameters there are in the current function. */ | |
10478270 | 609 | int unsafe_by_ref_count; |
ff6686d2 MJ |
610 | |
611 | /* Bitmap of BBs that can cause the function to "stop" progressing by | |
612 | returning, throwing externally, looping infinitely or calling a function | |
613 | which might abort etc.. */ | |
614 | bitmap final_bbs; | |
615 | ||
616 | /* Obstack to allocate various small structures required only when generating | |
617 | summary for a function. */ | |
618 | struct obstack gensum_obstack; | |
619 | ||
620 | /* Return false the function is apparently unsuitable for IPA-SRA based on it's | |
621 | attributes, return true otherwise. NODE is the cgraph node of the current | |
622 | function. */ | |
623 | ||
624 | static bool | |
625 | ipa_sra_preliminary_function_checks (cgraph_node *node) | |
626 | { | |
87f94429 | 627 | if (!node->can_change_signature) |
ff6686d2 MJ |
628 | { |
629 | if (dump_file) | |
630 | fprintf (dump_file, "Function cannot change signature.\n"); | |
631 | return false; | |
632 | } | |
633 | ||
634 | if (!tree_versionable_function_p (node->decl)) | |
635 | { | |
636 | if (dump_file) | |
637 | fprintf (dump_file, "Function is not versionable.\n"); | |
638 | return false; | |
639 | } | |
640 | ||
641 | if (!opt_for_fn (node->decl, optimize) | |
642 | || !opt_for_fn (node->decl, flag_ipa_sra)) | |
643 | { | |
644 | if (dump_file) | |
645 | fprintf (dump_file, "Not optimizing or IPA-SRA turned off for this " | |
646 | "function.\n"); | |
647 | return false; | |
648 | } | |
649 | ||
650 | if (DECL_VIRTUAL_P (node->decl)) | |
651 | { | |
652 | if (dump_file) | |
653 | fprintf (dump_file, "Function is a virtual method.\n"); | |
654 | return false; | |
655 | } | |
656 | ||
657 | struct function *fun = DECL_STRUCT_FUNCTION (node->decl); | |
658 | if (fun->stdarg) | |
659 | { | |
660 | if (dump_file) | |
661 | fprintf (dump_file, "Function uses stdarg. \n"); | |
662 | return false; | |
663 | } | |
664 | ||
ff6686d2 MJ |
665 | if (DECL_DISREGARD_INLINE_LIMITS (node->decl)) |
666 | { | |
667 | if (dump_file) | |
668 | fprintf (dump_file, "Always inline function will be inlined " | |
669 | "anyway. \n"); | |
670 | return false; | |
671 | } | |
672 | ||
673 | return true; | |
674 | } | |
675 | ||
676 | /* Print access tree starting at ACCESS to F. */ | |
677 | ||
678 | static void | |
679 | dump_gensum_access (FILE *f, gensum_param_access *access, unsigned indent) | |
680 | { | |
681 | fprintf (f, " "); | |
682 | for (unsigned i = 0; i < indent; i++) | |
683 | fprintf (f, " "); | |
684 | fprintf (f, " * Access to offset: " HOST_WIDE_INT_PRINT_DEC, | |
685 | access->offset); | |
686 | fprintf (f, ", size: " HOST_WIDE_INT_PRINT_DEC, access->size); | |
687 | fprintf (f, ", type: "); | |
688 | print_generic_expr (f, access->type); | |
689 | fprintf (f, ", alias_ptr_type: "); | |
690 | print_generic_expr (f, access->alias_ptr_type); | |
10478270 MJ |
691 | fprintf (f, ", load_count: "); |
692 | access->load_count.dump (f); | |
ff6686d2 MJ |
693 | fprintf (f, ", nonarg: %u, reverse: %u\n", access->nonarg, access->reverse); |
694 | for (gensum_param_access *ch = access->first_child; | |
695 | ch; | |
696 | ch = ch->next_sibling) | |
697 | dump_gensum_access (f, ch, indent + 2); | |
698 | } | |
699 | ||
700 | ||
701 | /* Print access tree starting at ACCESS to F. */ | |
702 | ||
703 | static void | |
704 | dump_isra_access (FILE *f, param_access *access) | |
705 | { | |
706 | fprintf (f, " * Access to unit offset: %u", access->unit_offset); | |
707 | fprintf (f, ", unit size: %u", access->unit_size); | |
708 | fprintf (f, ", type: "); | |
709 | print_generic_expr (f, access->type); | |
710 | fprintf (f, ", alias_ptr_type: "); | |
711 | print_generic_expr (f, access->alias_ptr_type); | |
712 | if (access->certain) | |
713 | fprintf (f, ", certain"); | |
714 | else | |
c76b3bc5 | 715 | fprintf (f, ", not certain"); |
ff6686d2 MJ |
716 | if (access->reverse) |
717 | fprintf (f, ", reverse"); | |
718 | fprintf (f, "\n"); | |
719 | } | |
720 | ||
721 | /* Dump access tree starting at ACCESS to stderr. */ | |
722 | ||
723 | DEBUG_FUNCTION void | |
724 | debug_isra_access (param_access *access) | |
725 | { | |
726 | dump_isra_access (stderr, access); | |
727 | } | |
728 | ||
729 | /* Dump DESC to F. */ | |
730 | ||
731 | static void | |
732 | dump_gensum_param_descriptor (FILE *f, gensum_param_desc *desc) | |
733 | { | |
734 | if (desc->locally_unused) | |
735 | fprintf (f, " unused with %i call_uses\n", desc->call_uses); | |
736 | if (!desc->split_candidate) | |
737 | { | |
738 | fprintf (f, " not a candidate\n"); | |
739 | return; | |
740 | } | |
741 | if (desc->by_ref) | |
f2cf4c61 MJ |
742 | fprintf (f, " %s%s by_ref with %u pass throughs\n", |
743 | desc->safe_ref ? "safe" : "unsafe", | |
744 | desc->conditionally_dereferenceable | |
745 | ? " conditionally_dereferenceable" : " ok", | |
746 | desc->ptr_pt_count); | |
ff6686d2 MJ |
747 | |
748 | for (gensum_param_access *acc = desc->accesses; acc; acc = acc->next_sibling) | |
749 | dump_gensum_access (f, acc, 2); | |
750 | } | |
751 | ||
dfea3d6f | 752 | /* Dump all parameter descriptors in IFS, assuming it describes FNDECL, to |
ff6686d2 MJ |
753 | F. */ |
754 | ||
755 | static void | |
756 | dump_gensum_param_descriptors (FILE *f, tree fndecl, | |
757 | vec<gensum_param_desc> *param_descriptions) | |
758 | { | |
759 | tree parm = DECL_ARGUMENTS (fndecl); | |
760 | for (unsigned i = 0; | |
761 | i < param_descriptions->length (); | |
762 | ++i, parm = DECL_CHAIN (parm)) | |
763 | { | |
764 | fprintf (f, " Descriptor for parameter %i ", i); | |
765 | print_generic_expr (f, parm, TDF_UID); | |
766 | fprintf (f, "\n"); | |
767 | dump_gensum_param_descriptor (f, &(*param_descriptions)[i]); | |
768 | } | |
769 | } | |
770 | ||
771 | ||
e3a5cc32 MJ |
772 | /* Dump DESC to F. If HINTS is true, also dump IPA-analysis computed |
773 | hints. */ | |
ff6686d2 MJ |
774 | |
775 | static void | |
e3a5cc32 | 776 | dump_isra_param_descriptor (FILE *f, isra_param_desc *desc, bool hints) |
ff6686d2 MJ |
777 | { |
778 | if (desc->locally_unused) | |
779 | { | |
780 | fprintf (f, " (locally) unused\n"); | |
781 | } | |
782 | if (!desc->split_candidate) | |
783 | { | |
f2cf4c61 MJ |
784 | fprintf (f, " not a candidate for splitting"); |
785 | if (hints && desc->by_ref && desc->safe_size_set) | |
786 | fprintf (f, ", safe_size: %u", (unsigned) desc->safe_size); | |
787 | fprintf (f, "\n"); | |
ff6686d2 MJ |
788 | return; |
789 | } | |
e3a5cc32 | 790 | fprintf (f, " param_size_limit: %u, size_reached: %u%s", |
ff6686d2 MJ |
791 | desc->param_size_limit, desc->size_reached, |
792 | desc->by_ref ? ", by_ref" : ""); | |
f2cf4c61 MJ |
793 | if (desc->by_ref && desc->conditionally_dereferenceable) |
794 | fprintf (f, ", conditionally_dereferenceable"); | |
e3a5cc32 MJ |
795 | if (hints) |
796 | { | |
797 | if (desc->by_ref && !desc->not_specially_constructed) | |
798 | fprintf (f, ", args_specially_constructed"); | |
f2cf4c61 MJ |
799 | if (desc->by_ref && desc->safe_size_set) |
800 | fprintf (f, ", safe_size: %u", (unsigned) desc->safe_size); | |
e3a5cc32 MJ |
801 | } |
802 | fprintf (f, "\n"); | |
ff6686d2 MJ |
803 | |
804 | for (unsigned i = 0; i < vec_safe_length (desc->accesses); ++i) | |
805 | { | |
806 | param_access *access = (*desc->accesses)[i]; | |
807 | dump_isra_access (f, access); | |
808 | } | |
809 | } | |
810 | ||
e3a5cc32 MJ |
811 | /* Dump all parameter descriptors in IFS, assuming it describes FNDECL, to F. |
812 | If HINTS is true, also dump IPA-analysis computed hints. */ | |
ff6686d2 MJ |
813 | |
814 | static void | |
e3a5cc32 MJ |
815 | dump_isra_param_descriptors (FILE *f, tree fndecl, isra_func_summary *ifs, |
816 | bool hints) | |
ff6686d2 MJ |
817 | { |
818 | tree parm = DECL_ARGUMENTS (fndecl); | |
819 | if (!ifs->m_parameters) | |
820 | { | |
821 | fprintf (f, " parameter descriptors not available\n"); | |
822 | return; | |
823 | } | |
824 | ||
825 | for (unsigned i = 0; | |
826 | i < ifs->m_parameters->length (); | |
827 | ++i, parm = DECL_CHAIN (parm)) | |
828 | { | |
829 | fprintf (f, " Descriptor for parameter %i ", i); | |
830 | print_generic_expr (f, parm, TDF_UID); | |
831 | fprintf (f, "\n"); | |
e3a5cc32 | 832 | dump_isra_param_descriptor (f, &(*ifs->m_parameters)[i], hints); |
ff6686d2 MJ |
833 | } |
834 | } | |
835 | ||
836 | /* Add SRC to inputs of PARAM_FLOW, unless it would exceed storage. If the | |
837 | function fails return false, otherwise return true. SRC must fit into an | |
838 | unsigned char. Used for purposes of transitive unused parameter | |
839 | removal. */ | |
840 | ||
841 | static bool | |
842 | add_src_to_param_flow (isra_param_flow *param_flow, int src) | |
843 | { | |
844 | gcc_checking_assert (src >= 0 && src <= UCHAR_MAX); | |
845 | if (param_flow->length == IPA_SRA_MAX_PARAM_FLOW_LEN) | |
846 | return false; | |
847 | ||
848 | param_flow->inputs[(int) param_flow->length] = src; | |
849 | param_flow->length++; | |
850 | return true; | |
851 | } | |
852 | ||
853 | /* Add a SRC to the inputs of PARAM_FLOW unless it is already there and assert | |
854 | it is the only input. Used for purposes of transitive parameter | |
855 | splitting. */ | |
856 | ||
857 | static void | |
858 | set_single_param_flow_source (isra_param_flow *param_flow, int src) | |
859 | { | |
860 | gcc_checking_assert (src >= 0 && src <= UCHAR_MAX); | |
861 | if (param_flow->length == 0) | |
862 | { | |
863 | param_flow->inputs[0] = src; | |
864 | param_flow->length = 1; | |
865 | } | |
866 | else if (param_flow->length == 1) | |
867 | gcc_assert (param_flow->inputs[0] == src); | |
868 | else | |
869 | gcc_unreachable (); | |
870 | } | |
871 | ||
872 | /* Assert that there is only a single value in PARAM_FLOW's inputs and return | |
873 | it. */ | |
874 | ||
875 | static unsigned | |
876 | get_single_param_flow_source (const isra_param_flow *param_flow) | |
877 | { | |
878 | gcc_assert (param_flow->length == 1); | |
879 | return param_flow->inputs[0]; | |
880 | } | |
881 | ||
882 | /* Inspect all uses of NAME and simple arithmetic calculations involving NAME | |
1980ffec MJ |
883 | in FUN represented with NODE and return a negative number if any of them is |
884 | used for something else than either an actual call argument, simple | |
885 | arithmetic operation or debug statement. If there are no such uses, return | |
886 | the number of actual arguments that this parameter eventually feeds to (or | |
887 | zero if there is none). For any such parameter, mark PARM_NUM as one of its | |
888 | sources. ANALYZED is a bitmap that tracks which SSA names we have already | |
889 | started investigating. */ | |
ff6686d2 MJ |
890 | |
891 | static int | |
1980ffec MJ |
892 | isra_track_scalar_value_uses (function *fun, cgraph_node *node, tree name, |
893 | int parm_num, bitmap analyzed) | |
ff6686d2 MJ |
894 | { |
895 | int res = 0; | |
896 | imm_use_iterator imm_iter; | |
897 | gimple *stmt; | |
898 | ||
899 | FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name) | |
900 | { | |
901 | if (is_gimple_debug (stmt)) | |
902 | continue; | |
903 | ||
904 | /* TODO: We could handle at least const builtin functions like arithmetic | |
905 | operations below. */ | |
906 | if (is_gimple_call (stmt)) | |
907 | { | |
908 | int all_uses = 0; | |
909 | use_operand_p use_p; | |
910 | FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter) | |
911 | all_uses++; | |
912 | ||
913 | gcall *call = as_a <gcall *> (stmt); | |
914 | unsigned arg_count; | |
915 | if (gimple_call_internal_p (call) | |
916 | || (arg_count = gimple_call_num_args (call)) == 0) | |
917 | { | |
918 | res = -1; | |
640296c3 | 919 | break; |
ff6686d2 MJ |
920 | } |
921 | ||
922 | cgraph_edge *cs = node->get_edge (stmt); | |
923 | gcc_checking_assert (cs); | |
924 | isra_call_summary *csum = call_sums->get_create (cs); | |
925 | csum->init_inputs (arg_count); | |
926 | ||
927 | int simple_uses = 0; | |
928 | for (unsigned i = 0; i < arg_count; i++) | |
929 | if (gimple_call_arg (call, i) == name) | |
930 | { | |
931 | if (!add_src_to_param_flow (&csum->m_arg_flow[i], parm_num)) | |
932 | { | |
933 | simple_uses = -1; | |
934 | break; | |
935 | } | |
936 | simple_uses++; | |
937 | } | |
938 | ||
939 | if (simple_uses < 0 | |
940 | || all_uses != simple_uses) | |
941 | { | |
942 | res = -1; | |
640296c3 | 943 | break; |
ff6686d2 MJ |
944 | } |
945 | res += all_uses; | |
946 | } | |
1980ffec MJ |
947 | else if (!stmt_unremovable_because_of_non_call_eh_p (fun, stmt) |
948 | && ((is_gimple_assign (stmt) && !gimple_has_volatile_ops (stmt)) | |
949 | || gimple_code (stmt) == GIMPLE_PHI)) | |
ff6686d2 MJ |
950 | { |
951 | tree lhs; | |
952 | if (gimple_code (stmt) == GIMPLE_PHI) | |
953 | lhs = gimple_phi_result (stmt); | |
954 | else | |
955 | lhs = gimple_assign_lhs (stmt); | |
956 | ||
957 | if (TREE_CODE (lhs) != SSA_NAME) | |
958 | { | |
959 | res = -1; | |
640296c3 | 960 | break; |
ff6686d2 MJ |
961 | } |
962 | gcc_assert (!gimple_vdef (stmt)); | |
963 | if (bitmap_set_bit (analyzed, SSA_NAME_VERSION (lhs))) | |
964 | { | |
1980ffec | 965 | int tmp = isra_track_scalar_value_uses (fun, node, lhs, parm_num, |
ff6686d2 MJ |
966 | analyzed); |
967 | if (tmp < 0) | |
968 | { | |
969 | res = tmp; | |
640296c3 | 970 | break; |
ff6686d2 MJ |
971 | } |
972 | res += tmp; | |
973 | } | |
974 | } | |
975 | else | |
976 | { | |
977 | res = -1; | |
640296c3 | 978 | break; |
ff6686d2 MJ |
979 | } |
980 | } | |
981 | return res; | |
982 | } | |
983 | ||
984 | /* Inspect all uses of PARM, which must be a gimple register, in FUN (which is | |
985 | also described by NODE) and simple arithmetic calculations involving PARM | |
986 | and return false if any of them is used for something else than either an | |
987 | actual call argument, simple arithmetic operation or debug statement. If | |
988 | there are no such uses, return true and store the number of actual arguments | |
989 | that this parameter eventually feeds to (or zero if there is none) to | |
990 | *CALL_USES_P. For any such parameter, mark PARM_NUM as one of its | |
991 | sources. | |
992 | ||
993 | This function is similar to ptr_parm_has_nonarg_uses but its results are | |
994 | meant for unused parameter removal, as opposed to splitting of parameters | |
c76b3bc5 | 995 | passed by reference or converting them to passed by value. */ |
ff6686d2 MJ |
996 | |
997 | static bool | |
998 | isra_track_scalar_param_local_uses (function *fun, cgraph_node *node, tree parm, | |
999 | int parm_num, int *call_uses_p) | |
1000 | { | |
1001 | gcc_checking_assert (is_gimple_reg (parm)); | |
1002 | ||
1003 | tree name = ssa_default_def (fun, parm); | |
1004 | if (!name || has_zero_uses (name)) | |
1005 | { | |
1006 | *call_uses_p = 0; | |
1007 | return false; | |
1008 | } | |
1009 | ||
1010 | /* Edge summaries can only handle callers with fewer than 256 parameters. */ | |
1011 | if (parm_num > UCHAR_MAX) | |
1012 | return true; | |
1013 | ||
1014 | bitmap analyzed = BITMAP_ALLOC (NULL); | |
1980ffec MJ |
1015 | int call_uses = isra_track_scalar_value_uses (fun, node, name, parm_num, |
1016 | analyzed); | |
ff6686d2 MJ |
1017 | BITMAP_FREE (analyzed); |
1018 | if (call_uses < 0) | |
1019 | return true; | |
1020 | *call_uses_p = call_uses; | |
1021 | return false; | |
1022 | } | |
1023 | ||
1024 | /* Scan immediate uses of a default definition SSA name of a parameter PARM and | |
1025 | examine whether there are any nonarg uses that are not actual arguments or | |
1026 | otherwise infeasible uses. If so, return true, otherwise return false. | |
1027 | Create pass-through IPA flow records for any direct uses as argument calls | |
1028 | and if returning false, store their number into *PT_COUNT_P. NODE and FUN | |
1029 | must represent the function that is currently analyzed, PARM_NUM must be the | |
1030 | index of the analyzed parameter. | |
1031 | ||
1032 | This function is similar to isra_track_scalar_param_local_uses but its | |
1033 | results are meant for splitting of parameters passed by reference or turning | |
1034 | them into bits passed by value, as opposed to generic unused parameter | |
c76b3bc5 | 1035 | removal. */ |
ff6686d2 MJ |
1036 | |
1037 | static bool | |
1038 | ptr_parm_has_nonarg_uses (cgraph_node *node, function *fun, tree parm, | |
1039 | int parm_num, unsigned *pt_count_p) | |
1040 | { | |
1041 | imm_use_iterator ui; | |
1042 | gimple *stmt; | |
1043 | tree name = ssa_default_def (fun, parm); | |
1044 | bool ret = false; | |
1045 | unsigned pt_count = 0; | |
1046 | ||
1047 | if (!name || has_zero_uses (name)) | |
1048 | return false; | |
1049 | ||
1050 | /* Edge summaries can only handle callers with fewer than 256 parameters. */ | |
1051 | if (parm_num > UCHAR_MAX) | |
1052 | return true; | |
1053 | ||
1054 | FOR_EACH_IMM_USE_STMT (stmt, ui, name) | |
1055 | { | |
1056 | unsigned uses_ok = 0; | |
1057 | use_operand_p use_p; | |
1058 | ||
1059 | if (is_gimple_debug (stmt)) | |
1060 | continue; | |
1061 | ||
1062 | if (gimple_assign_single_p (stmt)) | |
1063 | { | |
1064 | tree rhs = gimple_assign_rhs1 (stmt); | |
23cd18c6 RB |
1065 | if (!TREE_THIS_VOLATILE (rhs)) |
1066 | { | |
1067 | while (handled_component_p (rhs)) | |
1068 | rhs = TREE_OPERAND (rhs, 0); | |
1069 | if (TREE_CODE (rhs) == MEM_REF | |
1070 | && TREE_OPERAND (rhs, 0) == name | |
1071 | && integer_zerop (TREE_OPERAND (rhs, 1)) | |
1072 | && types_compatible_p (TREE_TYPE (rhs), | |
1073 | TREE_TYPE (TREE_TYPE (name)))) | |
1074 | uses_ok++; | |
1075 | } | |
ff6686d2 MJ |
1076 | } |
1077 | else if (is_gimple_call (stmt)) | |
1078 | { | |
1079 | gcall *call = as_a <gcall *> (stmt); | |
1080 | unsigned arg_count; | |
1081 | if (gimple_call_internal_p (call) | |
1082 | || (arg_count = gimple_call_num_args (call)) == 0) | |
1083 | { | |
1084 | ret = true; | |
640296c3 | 1085 | break; |
ff6686d2 MJ |
1086 | } |
1087 | ||
1088 | cgraph_edge *cs = node->get_edge (stmt); | |
1089 | gcc_checking_assert (cs); | |
1090 | isra_call_summary *csum = call_sums->get_create (cs); | |
1091 | csum->init_inputs (arg_count); | |
1092 | ||
1093 | for (unsigned i = 0; i < arg_count; ++i) | |
1094 | { | |
1095 | tree arg = gimple_call_arg (stmt, i); | |
1096 | ||
1097 | if (arg == name) | |
1098 | { | |
1099 | /* TODO: Allow &MEM_REF[name + offset] here, | |
1100 | ipa_param_body_adjustments::modify_call_stmt has to be | |
1101 | adjusted too. */ | |
1102 | csum->m_arg_flow[i].pointer_pass_through = true; | |
1103 | set_single_param_flow_source (&csum->m_arg_flow[i], parm_num); | |
1104 | pt_count++; | |
1105 | uses_ok++; | |
1106 | continue; | |
1107 | } | |
1108 | ||
23cd18c6 RB |
1109 | if (!TREE_THIS_VOLATILE (arg)) |
1110 | { | |
1111 | while (handled_component_p (arg)) | |
1112 | arg = TREE_OPERAND (arg, 0); | |
1113 | if (TREE_CODE (arg) == MEM_REF | |
1114 | && TREE_OPERAND (arg, 0) == name | |
1115 | && integer_zerop (TREE_OPERAND (arg, 1)) | |
1116 | && types_compatible_p (TREE_TYPE (arg), | |
1117 | TREE_TYPE (TREE_TYPE (name)))) | |
1118 | uses_ok++; | |
1119 | } | |
ff6686d2 MJ |
1120 | } |
1121 | } | |
1122 | ||
1123 | /* If the number of valid uses does not match the number of | |
1124 | uses in this stmt there is an unhandled use. */ | |
1125 | unsigned all_uses = 0; | |
1126 | FOR_EACH_IMM_USE_ON_STMT (use_p, ui) | |
1127 | all_uses++; | |
1128 | ||
1129 | gcc_checking_assert (uses_ok <= all_uses); | |
1130 | if (uses_ok != all_uses) | |
1131 | { | |
1132 | ret = true; | |
640296c3 | 1133 | break; |
ff6686d2 MJ |
1134 | } |
1135 | } | |
1136 | ||
1137 | *pt_count_p = pt_count; | |
1138 | return ret; | |
1139 | } | |
1140 | ||
1141 | /* Initialize vector of parameter descriptors of NODE. Return true if there | |
1142 | are any candidates for splitting or unused aggregate parameter removal (the | |
1143 | function may return false if there are candidates for removal of register | |
e3a5cc32 | 1144 | parameters). */ |
ff6686d2 MJ |
1145 | |
1146 | static bool | |
1147 | create_parameter_descriptors (cgraph_node *node, | |
1148 | vec<gensum_param_desc> *param_descriptions) | |
1149 | { | |
1150 | function *fun = DECL_STRUCT_FUNCTION (node->decl); | |
1151 | bool ret = false; | |
1152 | ||
1153 | int num = 0; | |
1154 | for (tree parm = DECL_ARGUMENTS (node->decl); | |
1155 | parm; | |
1156 | parm = DECL_CHAIN (parm), num++) | |
1157 | { | |
1158 | const char *msg; | |
1159 | gensum_param_desc *desc = &(*param_descriptions)[num]; | |
1160 | /* param_descriptions vector is grown cleared in the caller. */ | |
1161 | desc->param_number = num; | |
1162 | decl2desc->put (parm, desc); | |
1163 | ||
1164 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1165 | print_generic_expr (dump_file, parm, TDF_UID); | |
1166 | ||
1167 | int scalar_call_uses; | |
1168 | tree type = TREE_TYPE (parm); | |
1169 | if (TREE_THIS_VOLATILE (parm)) | |
1170 | { | |
1171 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1172 | fprintf (dump_file, " not a candidate, is volatile\n"); | |
1173 | continue; | |
1174 | } | |
1175 | if (!is_gimple_reg_type (type) && is_va_list_type (type)) | |
1176 | { | |
1177 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1178 | fprintf (dump_file, " not a candidate, is a va_list type\n"); | |
1179 | continue; | |
1180 | } | |
1181 | if (TREE_ADDRESSABLE (parm)) | |
1182 | { | |
1183 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1184 | fprintf (dump_file, " not a candidate, is addressable\n"); | |
1185 | continue; | |
1186 | } | |
1187 | if (TREE_ADDRESSABLE (type)) | |
1188 | { | |
1189 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1190 | fprintf (dump_file, " not a candidate, type cannot be split\n"); | |
1191 | continue; | |
1192 | } | |
1193 | ||
1194 | if (is_gimple_reg (parm) | |
1195 | && !isra_track_scalar_param_local_uses (fun, node, parm, num, | |
1196 | &scalar_call_uses)) | |
1197 | { | |
1198 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1199 | fprintf (dump_file, " is a scalar with only %i call uses\n", | |
1200 | scalar_call_uses); | |
1201 | ||
1202 | desc->locally_unused = true; | |
1203 | desc->call_uses = scalar_call_uses; | |
1204 | } | |
1205 | ||
1206 | if (POINTER_TYPE_P (type)) | |
1207 | { | |
10478270 | 1208 | desc->by_ref = true; |
0e949530 MJ |
1209 | if (TREE_CODE (type) == REFERENCE_TYPE |
1210 | || (num == 0 | |
1211 | && TREE_CODE (TREE_TYPE (node->decl)) == METHOD_TYPE)) | |
1212 | desc->safe_ref = true; | |
1213 | else | |
1214 | desc->safe_ref = false; | |
ff6686d2 MJ |
1215 | type = TREE_TYPE (type); |
1216 | ||
1217 | if (TREE_CODE (type) == FUNCTION_TYPE | |
1218 | || TREE_CODE (type) == METHOD_TYPE) | |
1219 | { | |
1220 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1221 | fprintf (dump_file, " not a candidate, reference to " | |
1222 | "a function\n"); | |
1223 | continue; | |
1224 | } | |
1225 | if (TYPE_VOLATILE (type)) | |
1226 | { | |
1227 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1228 | fprintf (dump_file, " not a candidate, reference to " | |
1229 | "a volatile type\n"); | |
1230 | continue; | |
1231 | } | |
1232 | if (TREE_CODE (type) == ARRAY_TYPE | |
1233 | && TYPE_NONALIASED_COMPONENT (type)) | |
1234 | { | |
1235 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
f8cb8bcd JJ |
1236 | fprintf (dump_file, " not a candidate, reference to " |
1237 | "a nonaliased component array\n"); | |
ff6686d2 MJ |
1238 | continue; |
1239 | } | |
1240 | if (!is_gimple_reg (parm)) | |
1241 | { | |
1242 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1243 | fprintf (dump_file, " not a candidate, a reference which is " | |
1244 | "not a gimple register (probably addressable)\n"); | |
1245 | continue; | |
1246 | } | |
1247 | if (is_va_list_type (type)) | |
1248 | { | |
1249 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1250 | fprintf (dump_file, " not a candidate, reference to " | |
1251 | "a va list\n"); | |
1252 | continue; | |
1253 | } | |
1254 | if (ptr_parm_has_nonarg_uses (node, fun, parm, num, | |
1255 | &desc->ptr_pt_count)) | |
1256 | { | |
1257 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1258 | fprintf (dump_file, " not a candidate, reference has " | |
1259 | "nonarg uses\n"); | |
1260 | continue; | |
1261 | } | |
ff6686d2 MJ |
1262 | } |
1263 | else if (!AGGREGATE_TYPE_P (type)) | |
1264 | { | |
1265 | /* This is in an else branch because scalars passed by reference are | |
1266 | still candidates to be passed by value. */ | |
1267 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1268 | fprintf (dump_file, " not a candidate, not an aggregate\n"); | |
1269 | continue; | |
1270 | } | |
1271 | ||
1272 | if (!COMPLETE_TYPE_P (type)) | |
1273 | { | |
1274 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1275 | fprintf (dump_file, " not a candidate, not a complete type\n"); | |
1276 | continue; | |
1277 | } | |
1278 | if (!tree_fits_uhwi_p (TYPE_SIZE (type))) | |
1279 | { | |
1280 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1281 | fprintf (dump_file, " not a candidate, size not representable\n"); | |
1282 | continue; | |
1283 | } | |
1284 | unsigned HOST_WIDE_INT type_size | |
1285 | = tree_to_uhwi (TYPE_SIZE (type)) / BITS_PER_UNIT; | |
1286 | if (type_size == 0 | |
1287 | || type_size >= ISRA_ARG_SIZE_LIMIT) | |
1288 | { | |
1289 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1290 | fprintf (dump_file, " not a candidate, has zero or huge size\n"); | |
1291 | continue; | |
1292 | } | |
1293 | if (type_internals_preclude_sra_p (type, &msg)) | |
1294 | { | |
1295 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1296 | fprintf (dump_file, " not a candidate, %s\n", msg); | |
1297 | continue; | |
1298 | } | |
1299 | ||
1300 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1301 | fprintf (dump_file, " is a candidate\n"); | |
1302 | ||
1303 | ret = true; | |
1304 | desc->split_candidate = true; | |
10478270 MJ |
1305 | if (desc->by_ref && !desc->safe_ref) |
1306 | desc->deref_index = unsafe_by_ref_count++; | |
ff6686d2 MJ |
1307 | } |
1308 | return ret; | |
1309 | } | |
1310 | ||
1311 | /* Return pointer to descriptor of parameter DECL or NULL if it cannot be | |
1312 | found, which happens if DECL is for a static chain. */ | |
1313 | ||
1314 | static gensum_param_desc * | |
1315 | get_gensum_param_desc (tree decl) | |
1316 | { | |
e3a5cc32 MJ |
1317 | if (!decl2desc) |
1318 | return NULL; | |
ff6686d2 MJ |
1319 | gcc_checking_assert (TREE_CODE (decl) == PARM_DECL); |
1320 | gensum_param_desc **slot = decl2desc->get (decl); | |
1321 | if (!slot) | |
1322 | /* This can happen for static chains which we cannot handle so far. */ | |
1323 | return NULL; | |
1324 | gcc_checking_assert (*slot); | |
1325 | return *slot; | |
1326 | } | |
1327 | ||
1328 | ||
1329 | /* Remove parameter described by DESC from candidates for IPA-SRA splitting and | |
1330 | write REASON to the dump file if there is one. */ | |
1331 | ||
1332 | static void | |
1333 | disqualify_split_candidate (gensum_param_desc *desc, const char *reason) | |
1334 | { | |
1335 | if (!desc->split_candidate) | |
1336 | return; | |
1337 | ||
1338 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1339 | fprintf (dump_file, "! Disqualifying parameter number %i - %s\n", | |
1340 | desc->param_number, reason); | |
1341 | ||
1342 | desc->split_candidate = false; | |
1343 | } | |
1344 | ||
1345 | /* Remove DECL from candidates for IPA-SRA and write REASON to the dump file if | |
1346 | there is one. */ | |
1347 | ||
1348 | static void | |
1349 | disqualify_split_candidate (tree decl, const char *reason) | |
1350 | { | |
1351 | gensum_param_desc *desc = get_gensum_param_desc (decl); | |
1352 | if (desc) | |
1353 | disqualify_split_candidate (desc, reason); | |
1354 | } | |
1355 | ||
1356 | /* Allocate a new access to DESC and fill it in with OFFSET and SIZE. But | |
1357 | first, check that there are not too many of them already. If so, do not | |
1358 | allocate anything and return NULL. */ | |
1359 | ||
1360 | static gensum_param_access * | |
1361 | allocate_access (gensum_param_desc *desc, | |
1362 | HOST_WIDE_INT offset, HOST_WIDE_INT size) | |
1363 | { | |
1364 | if (desc->access_count | |
028d4092 | 1365 | == (unsigned) param_ipa_sra_max_replacements) |
ff6686d2 MJ |
1366 | { |
1367 | disqualify_split_candidate (desc, "Too many replacement candidates"); | |
1368 | return NULL; | |
1369 | } | |
1370 | ||
1371 | gensum_param_access *access | |
1372 | = (gensum_param_access *) obstack_alloc (&gensum_obstack, | |
1373 | sizeof (gensum_param_access)); | |
1374 | memset (access, 0, sizeof (*access)); | |
1375 | access->offset = offset; | |
1376 | access->size = size; | |
10478270 | 1377 | access->load_count = profile_count::zero (); |
ff6686d2 MJ |
1378 | return access; |
1379 | } | |
1380 | ||
1381 | /* In what context scan_expr_access has been called, whether it deals with a | |
9707b593 MJ |
1382 | load, a function argument, or a store. Please note that in rare |
1383 | circumstances when it is not clear if the access is a load or store, | |
1384 | ISRA_CTX_STORE is used too. */ | |
ff6686d2 MJ |
1385 | |
1386 | enum isra_scan_context {ISRA_CTX_LOAD, ISRA_CTX_ARG, ISRA_CTX_STORE}; | |
1387 | ||
1388 | /* Return an access describing memory access to the variable described by DESC | |
1389 | at OFFSET with SIZE in context CTX, starting at pointer to the linked list | |
dfea3d6f | 1390 | at a certain tree level FIRST. Attempt to create it and put into the |
ff6686d2 MJ |
1391 | appropriate place in the access tree if does not exist, but fail and return |
1392 | NULL if there are already too many accesses, if it would create a partially | |
dfea3d6f | 1393 | overlapping access or if an access would end up within a pre-existing |
ff6686d2 MJ |
1394 | non-call access. */ |
1395 | ||
1396 | static gensum_param_access * | |
1397 | get_access_1 (gensum_param_desc *desc, gensum_param_access **first, | |
1398 | HOST_WIDE_INT offset, HOST_WIDE_INT size, isra_scan_context ctx) | |
1399 | { | |
1400 | gensum_param_access *access = *first, **ptr = first; | |
1401 | ||
1402 | if (!access) | |
1403 | { | |
1404 | /* No pre-existing access at this level, just create it. */ | |
1405 | gensum_param_access *a = allocate_access (desc, offset, size); | |
1406 | if (!a) | |
1407 | return NULL; | |
1408 | *first = a; | |
1409 | return *first; | |
1410 | } | |
1411 | ||
1412 | if (access->offset >= offset + size) | |
1413 | { | |
1414 | /* We want to squeeze it in front of the very first access, just do | |
1415 | it. */ | |
1416 | gensum_param_access *r = allocate_access (desc, offset, size); | |
1417 | if (!r) | |
1418 | return NULL; | |
1419 | r->next_sibling = access; | |
1420 | *first = r; | |
1421 | return r; | |
1422 | } | |
1423 | ||
1424 | /* Skip all accesses that have to come before us until the next sibling is | |
1425 | already too far. */ | |
1426 | while (offset >= access->offset + access->size | |
1427 | && access->next_sibling | |
1428 | && access->next_sibling->offset < offset + size) | |
1429 | { | |
1430 | ptr = &access->next_sibling; | |
1431 | access = access->next_sibling; | |
1432 | } | |
1433 | ||
1434 | /* At this point we know we do not belong before access. */ | |
1435 | gcc_assert (access->offset < offset + size); | |
1436 | ||
1437 | if (access->offset == offset && access->size == size) | |
1438 | /* We found what we were looking for. */ | |
1439 | return access; | |
1440 | ||
1441 | if (access->offset <= offset | |
1442 | && access->offset + access->size >= offset + size) | |
1443 | { | |
1444 | /* We fit into access which is larger than us. We need to find/create | |
1445 | something below access. But we only allow nesting in call | |
1446 | arguments. */ | |
1447 | if (access->nonarg) | |
1448 | return NULL; | |
1449 | ||
1450 | return get_access_1 (desc, &access->first_child, offset, size, ctx); | |
1451 | } | |
1452 | ||
1453 | if (offset <= access->offset | |
1454 | && offset + size >= access->offset + access->size) | |
1455 | /* We are actually bigger than access, which fully fits into us, take its | |
1456 | place and make all accesses fitting into it its children. */ | |
1457 | { | |
1458 | /* But first, we only allow nesting in call arguments so check if that is | |
1459 | what we are trying to represent. */ | |
1460 | if (ctx != ISRA_CTX_ARG) | |
1461 | return NULL; | |
1462 | ||
1463 | gensum_param_access *r = allocate_access (desc, offset, size); | |
1464 | if (!r) | |
1465 | return NULL; | |
1466 | r->first_child = access; | |
1467 | ||
1468 | while (access->next_sibling | |
1469 | && access->next_sibling->offset < offset + size) | |
1470 | access = access->next_sibling; | |
1471 | if (access->offset + access->size > offset + size) | |
1472 | { | |
1473 | /* This must be a different access, which are sorted, so the | |
1474 | following must be true and this signals a partial overlap. */ | |
1475 | gcc_assert (access->offset > offset); | |
1476 | return NULL; | |
1477 | } | |
1478 | ||
1479 | r->next_sibling = access->next_sibling; | |
1480 | access->next_sibling = NULL; | |
1481 | *ptr = r; | |
1482 | return r; | |
1483 | } | |
1484 | ||
1485 | if (offset >= access->offset + access->size) | |
1486 | { | |
1487 | /* We belong after access. */ | |
1488 | gensum_param_access *r = allocate_access (desc, offset, size); | |
1489 | if (!r) | |
1490 | return NULL; | |
1491 | r->next_sibling = access->next_sibling; | |
1492 | access->next_sibling = r; | |
1493 | return r; | |
1494 | } | |
1495 | ||
1496 | if (offset < access->offset) | |
1497 | { | |
1498 | /* We know the following, otherwise we would have created a | |
1499 | super-access. */ | |
1500 | gcc_checking_assert (offset + size < access->offset + access->size); | |
1501 | return NULL; | |
1502 | } | |
1503 | ||
1504 | if (offset + size > access->offset + access->size) | |
1505 | { | |
1506 | /* Likewise. */ | |
1507 | gcc_checking_assert (offset > access->offset); | |
1508 | return NULL; | |
1509 | } | |
1510 | ||
1511 | gcc_unreachable (); | |
1512 | } | |
1513 | ||
1514 | /* Return an access describing memory access to the variable described by DESC | |
1515 | at OFFSET with SIZE in context CTX, mark it as used in context CTX. Attempt | |
1516 | to create if it does not exist, but fail and return NULL if there are | |
1517 | already too many accesses, if it would create a partially overlapping access | |
dfea3d6f | 1518 | or if an access would end up in a non-call access. */ |
ff6686d2 MJ |
1519 | |
1520 | static gensum_param_access * | |
1521 | get_access (gensum_param_desc *desc, HOST_WIDE_INT offset, HOST_WIDE_INT size, | |
1522 | isra_scan_context ctx) | |
1523 | { | |
1524 | gcc_checking_assert (desc->split_candidate); | |
1525 | ||
1526 | gensum_param_access *access = get_access_1 (desc, &desc->accesses, offset, | |
1527 | size, ctx); | |
1528 | if (!access) | |
1529 | { | |
1530 | disqualify_split_candidate (desc, | |
1531 | "Bad access overlap or too many accesses"); | |
1532 | return NULL; | |
1533 | } | |
1534 | ||
1535 | switch (ctx) | |
1536 | { | |
1537 | case ISRA_CTX_STORE: | |
1538 | gcc_assert (!desc->by_ref); | |
1539 | /* Fall-through */ | |
1540 | case ISRA_CTX_LOAD: | |
1541 | access->nonarg = true; | |
1542 | break; | |
1543 | case ISRA_CTX_ARG: | |
1544 | break; | |
1545 | } | |
1546 | ||
1547 | return access; | |
1548 | } | |
1549 | ||
1550 | /* Verify that parameter access tree starting with ACCESS is in good shape. | |
dfea3d6f | 1551 | PARENT_OFFSET and PARENT_SIZE are the corresponding fields of parent of |
ff6686d2 MJ |
1552 | ACCESS or zero if there is none. */ |
1553 | ||
1554 | static bool | |
1555 | verify_access_tree_1 (gensum_param_access *access, HOST_WIDE_INT parent_offset, | |
1556 | HOST_WIDE_INT parent_size) | |
1557 | { | |
1558 | while (access) | |
1559 | { | |
241a2c49 | 1560 | gcc_assert (access->offset >= 0 && access->size >= 0); |
ff6686d2 MJ |
1561 | |
1562 | if (parent_size != 0) | |
1563 | { | |
1564 | if (access->offset < parent_offset) | |
1565 | { | |
1566 | error ("Access offset before parent offset"); | |
1567 | return true; | |
1568 | } | |
1569 | if (access->size >= parent_size) | |
1570 | { | |
1571 | error ("Access size greater or equal to its parent size"); | |
1572 | return true; | |
1573 | } | |
1574 | if (access->offset + access->size > parent_offset + parent_size) | |
1575 | { | |
1576 | error ("Access terminates outside of its parent"); | |
1577 | return true; | |
1578 | } | |
1579 | } | |
1580 | ||
1581 | if (verify_access_tree_1 (access->first_child, access->offset, | |
1582 | access->size)) | |
1583 | return true; | |
1584 | ||
1585 | if (access->next_sibling | |
1586 | && (access->next_sibling->offset < access->offset + access->size)) | |
1587 | { | |
1588 | error ("Access overlaps with its sibling"); | |
1589 | return true; | |
1590 | } | |
1591 | ||
1592 | access = access->next_sibling; | |
1593 | } | |
1594 | return false; | |
1595 | } | |
1596 | ||
1597 | /* Verify that parameter access tree starting with ACCESS is in good shape, | |
1598 | halt compilation and dump the tree to stderr if not. */ | |
1599 | ||
1600 | DEBUG_FUNCTION void | |
1601 | isra_verify_access_tree (gensum_param_access *access) | |
1602 | { | |
1603 | if (verify_access_tree_1 (access, 0, 0)) | |
1604 | { | |
1605 | for (; access; access = access->next_sibling) | |
1606 | dump_gensum_access (stderr, access, 2); | |
1607 | internal_error ("IPA-SRA access verification failed"); | |
1608 | } | |
1609 | } | |
1610 | ||
1611 | ||
1612 | /* Callback of walk_stmt_load_store_addr_ops visit_addr used to determine | |
1613 | GIMPLE_ASM operands with memory constrains which cannot be scalarized. */ | |
1614 | ||
1615 | static bool | |
1616 | asm_visit_addr (gimple *, tree op, tree, void *) | |
1617 | { | |
1618 | op = get_base_address (op); | |
1619 | if (op | |
1620 | && TREE_CODE (op) == PARM_DECL) | |
1621 | disqualify_split_candidate (op, "Non-scalarizable GIMPLE_ASM operand."); | |
1622 | ||
1623 | return false; | |
1624 | } | |
1625 | ||
1626 | /* Mark a dereference of parameter identified by DESC of distance DIST in a | |
1627 | basic block BB, unless the BB has already been marked as a potentially | |
1628 | final. */ | |
1629 | ||
1630 | static void | |
1631 | mark_param_dereference (gensum_param_desc *desc, HOST_WIDE_INT dist, | |
10478270 | 1632 | basic_block bb) |
ff6686d2 MJ |
1633 | { |
1634 | gcc_assert (desc->by_ref); | |
1635 | gcc_checking_assert (desc->split_candidate); | |
1636 | ||
10478270 MJ |
1637 | if (desc->safe_ref |
1638 | || bitmap_bit_p (final_bbs, bb->index)) | |
ff6686d2 MJ |
1639 | return; |
1640 | ||
10478270 | 1641 | int idx = bb->index * unsafe_by_ref_count + desc->deref_index; |
ff6686d2 MJ |
1642 | if (bb_dereferences[idx] < dist) |
1643 | bb_dereferences[idx] = dist; | |
1644 | } | |
1645 | ||
1646 | /* Return true, if any potential replacements should use NEW_TYPE as opposed to | |
1647 | previously recorded OLD_TYPE. */ | |
1648 | ||
1649 | static bool | |
1650 | type_prevails_p (tree old_type, tree new_type) | |
1651 | { | |
1652 | if (old_type == new_type) | |
1653 | return false; | |
1654 | ||
1655 | /* Non-aggregates are always better. */ | |
1656 | if (!is_gimple_reg_type (old_type) | |
1657 | && is_gimple_reg_type (new_type)) | |
1658 | return true; | |
1659 | if (is_gimple_reg_type (old_type) | |
1660 | && !is_gimple_reg_type (new_type)) | |
1661 | return false; | |
1662 | ||
1663 | /* Prefer any complex or vector type over any other scalar type. */ | |
1664 | if (TREE_CODE (old_type) != COMPLEX_TYPE | |
1665 | && TREE_CODE (old_type) != VECTOR_TYPE | |
1666 | && (TREE_CODE (new_type) == COMPLEX_TYPE | |
1667 | || TREE_CODE (new_type) == VECTOR_TYPE)) | |
1668 | return true; | |
1669 | if ((TREE_CODE (old_type) == COMPLEX_TYPE | |
1670 | || TREE_CODE (old_type) == VECTOR_TYPE) | |
1671 | && TREE_CODE (new_type) != COMPLEX_TYPE | |
1672 | && TREE_CODE (new_type) != VECTOR_TYPE) | |
1673 | return false; | |
1674 | ||
1675 | /* Use the integral type with the bigger precision. */ | |
1676 | if (INTEGRAL_TYPE_P (old_type) | |
1677 | && INTEGRAL_TYPE_P (new_type)) | |
1678 | return (TYPE_PRECISION (new_type) > TYPE_PRECISION (old_type)); | |
1679 | ||
1680 | /* Attempt to disregard any integral type with non-full precision. */ | |
1681 | if (INTEGRAL_TYPE_P (old_type) | |
1682 | && (TREE_INT_CST_LOW (TYPE_SIZE (old_type)) | |
1683 | != TYPE_PRECISION (old_type))) | |
1684 | return true; | |
1685 | if (INTEGRAL_TYPE_P (new_type) | |
1686 | && (TREE_INT_CST_LOW (TYPE_SIZE (new_type)) | |
1687 | != TYPE_PRECISION (new_type))) | |
1688 | return false; | |
1689 | /* Stabilize the selection. */ | |
1690 | return TYPE_UID (old_type) < TYPE_UID (new_type); | |
1691 | } | |
1692 | ||
1693 | /* When scanning an expression which is a call argument, this structure | |
dfea3d6f | 1694 | specifies the call and the position of the argument. */ |
ff6686d2 MJ |
1695 | |
1696 | struct scan_call_info | |
1697 | { | |
1698 | /* Call graph edge representing the call. */ | |
1699 | cgraph_edge *cs; | |
1700 | /* Total number of arguments in the call. */ | |
1701 | unsigned argument_count; | |
1702 | /* Number of the actual argument being scanned. */ | |
1703 | unsigned arg_idx; | |
1704 | }; | |
1705 | ||
1706 | /* Record use of ACCESS which belongs to a parameter described by DESC in a | |
1707 | call argument described by CALL_INFO. */ | |
1708 | ||
1709 | static void | |
1710 | record_nonregister_call_use (gensum_param_desc *desc, | |
1711 | scan_call_info *call_info, | |
1712 | unsigned unit_offset, unsigned unit_size) | |
1713 | { | |
1714 | isra_call_summary *csum = call_sums->get_create (call_info->cs); | |
1715 | csum->init_inputs (call_info->argument_count); | |
1716 | ||
1717 | isra_param_flow *param_flow = &csum->m_arg_flow[call_info->arg_idx]; | |
1718 | param_flow->aggregate_pass_through = true; | |
1719 | set_single_param_flow_source (param_flow, desc->param_number); | |
1720 | param_flow->unit_offset = unit_offset; | |
1721 | param_flow->unit_size = unit_size; | |
1722 | desc->call_uses++; | |
1723 | } | |
1724 | ||
1725 | /* Callback of walk_aliased_vdefs, just mark that there was a possible | |
c76b3bc5 | 1726 | modification. */ |
ff6686d2 MJ |
1727 | |
1728 | static bool | |
1729 | mark_maybe_modified (ao_ref *, tree, void *data) | |
1730 | { | |
1731 | bool *maybe_modified = (bool *) data; | |
1732 | *maybe_modified = true; | |
1733 | return true; | |
1734 | } | |
1735 | ||
1736 | /* Analyze expression EXPR from GIMPLE for accesses to parameters. CTX | |
1737 | specifies whether EXPR is used in a load, store or as an argument call. BB | |
1738 | must be the basic block in which expr resides. If CTX specifies call | |
dfea3d6f | 1739 | argument context, CALL_INFO must describe that call and argument position, |
ff6686d2 MJ |
1740 | otherwise it is ignored. */ |
1741 | ||
1742 | static void | |
1743 | scan_expr_access (tree expr, gimple *stmt, isra_scan_context ctx, | |
1744 | basic_block bb, scan_call_info *call_info = NULL) | |
1745 | { | |
1746 | poly_int64 poffset, psize, pmax_size; | |
1747 | HOST_WIDE_INT offset, size, max_size; | |
1748 | tree base; | |
1749 | bool deref = false; | |
1750 | bool reverse; | |
1751 | ||
6539bbc1 MJ |
1752 | if (TREE_CODE (expr) == ADDR_EXPR) |
1753 | { | |
1754 | if (ctx == ISRA_CTX_ARG) | |
1755 | return; | |
1756 | tree t = get_base_address (TREE_OPERAND (expr, 0)); | |
1757 | if (TREE_CODE (t) == VAR_DECL && !TREE_STATIC (t)) | |
1758 | loaded_decls->add (t); | |
1759 | return; | |
1760 | } | |
1761 | if (TREE_CODE (expr) == SSA_NAME | |
1762 | || CONSTANT_CLASS_P (expr)) | |
1763 | return; | |
1764 | ||
ff6686d2 MJ |
1765 | if (TREE_CODE (expr) == BIT_FIELD_REF |
1766 | || TREE_CODE (expr) == IMAGPART_EXPR | |
1767 | || TREE_CODE (expr) == REALPART_EXPR) | |
1768 | expr = TREE_OPERAND (expr, 0); | |
1769 | ||
1770 | base = get_ref_base_and_extent (expr, &poffset, &psize, &pmax_size, &reverse); | |
1771 | ||
1772 | if (TREE_CODE (base) == MEM_REF) | |
1773 | { | |
1774 | tree op = TREE_OPERAND (base, 0); | |
1775 | if (TREE_CODE (op) != SSA_NAME | |
1776 | || !SSA_NAME_IS_DEFAULT_DEF (op)) | |
1777 | return; | |
1778 | base = SSA_NAME_VAR (op); | |
1779 | if (!base) | |
1780 | return; | |
1781 | deref = true; | |
1782 | } | |
e3a5cc32 MJ |
1783 | else if (TREE_CODE (base) == VAR_DECL |
1784 | && !TREE_STATIC (base) | |
1785 | && (ctx == ISRA_CTX_ARG | |
1786 | || ctx == ISRA_CTX_LOAD)) | |
1787 | loaded_decls->add (base); | |
1788 | ||
ff6686d2 MJ |
1789 | if (TREE_CODE (base) != PARM_DECL) |
1790 | return; | |
1791 | ||
1792 | gensum_param_desc *desc = get_gensum_param_desc (base); | |
1793 | if (!desc || !desc->split_candidate) | |
1794 | return; | |
1795 | ||
1796 | if (!poffset.is_constant (&offset) | |
1797 | || !psize.is_constant (&size) | |
1798 | || !pmax_size.is_constant (&max_size)) | |
1799 | { | |
1800 | disqualify_split_candidate (desc, "Encountered a polynomial-sized " | |
1801 | "access."); | |
1802 | return; | |
1803 | } | |
1804 | if (size < 0 || size != max_size) | |
1805 | { | |
1806 | disqualify_split_candidate (desc, "Encountered a variable sized access."); | |
1807 | return; | |
1808 | } | |
1809 | if (TREE_CODE (expr) == COMPONENT_REF | |
1810 | && DECL_BIT_FIELD (TREE_OPERAND (expr, 1))) | |
1811 | { | |
1812 | disqualify_split_candidate (desc, "Encountered a bit-field access."); | |
1813 | return; | |
1814 | } | |
5a4d0da4 MJ |
1815 | if (offset < 0) |
1816 | { | |
1817 | disqualify_split_candidate (desc, "Encountered an access at a " | |
1818 | "negative offset."); | |
1819 | return; | |
1820 | } | |
ff6686d2 MJ |
1821 | gcc_assert ((offset % BITS_PER_UNIT) == 0); |
1822 | gcc_assert ((size % BITS_PER_UNIT) == 0); | |
1823 | if ((offset / BITS_PER_UNIT) >= (UINT_MAX - ISRA_ARG_SIZE_LIMIT) | |
1824 | || (size / BITS_PER_UNIT) >= ISRA_ARG_SIZE_LIMIT) | |
1825 | { | |
1826 | disqualify_split_candidate (desc, "Encountered an access with too big " | |
1827 | "offset or size"); | |
1828 | return; | |
1829 | } | |
1830 | ||
1831 | tree type = TREE_TYPE (expr); | |
1832 | unsigned int exp_align = get_object_alignment (expr); | |
1833 | ||
1834 | if (exp_align < TYPE_ALIGN (type)) | |
1835 | { | |
1836 | disqualify_split_candidate (desc, "Underaligned access."); | |
1837 | return; | |
1838 | } | |
1839 | ||
1840 | if (deref) | |
1841 | { | |
1842 | if (!desc->by_ref) | |
1843 | { | |
1844 | disqualify_split_candidate (desc, "Dereferencing a non-reference."); | |
1845 | return; | |
1846 | } | |
1847 | else if (ctx == ISRA_CTX_STORE) | |
1848 | { | |
1849 | disqualify_split_candidate (desc, "Storing to data passed by " | |
1850 | "reference."); | |
1851 | return; | |
1852 | } | |
1853 | ||
1854 | if (!aa_walking_limit) | |
1855 | { | |
1856 | disqualify_split_candidate (desc, "Out of alias analysis step " | |
1857 | "limit."); | |
1858 | return; | |
1859 | } | |
1860 | ||
1861 | gcc_checking_assert (gimple_vuse (stmt)); | |
1862 | bool maybe_modified = false; | |
1863 | ao_ref ar; | |
1864 | ||
1865 | ao_ref_init (&ar, expr); | |
1866 | bitmap visited = BITMAP_ALLOC (NULL); | |
1867 | int walked = walk_aliased_vdefs (&ar, gimple_vuse (stmt), | |
1868 | mark_maybe_modified, &maybe_modified, | |
1869 | &visited, NULL, aa_walking_limit); | |
1870 | BITMAP_FREE (visited); | |
1871 | if (walked > 0) | |
1872 | { | |
1873 | gcc_assert (aa_walking_limit > walked); | |
1874 | aa_walking_limit = aa_walking_limit - walked; | |
1875 | } | |
1876 | if (walked < 0) | |
1877 | aa_walking_limit = 0; | |
1878 | if (maybe_modified || walked < 0) | |
1879 | { | |
1880 | disqualify_split_candidate (desc, "Data passed by reference possibly " | |
1881 | "modified through an alias."); | |
1882 | return; | |
1883 | } | |
1884 | else | |
1885 | mark_param_dereference (desc, offset + size, bb); | |
1886 | } | |
1887 | else | |
1888 | /* Pointer parameters with direct uses should have been ruled out by | |
dfea3d6f | 1889 | analyzing SSA default def when looking at the parameters. */ |
ff6686d2 MJ |
1890 | gcc_assert (!desc->by_ref); |
1891 | ||
1892 | gensum_param_access *access = get_access (desc, offset, size, ctx); | |
1893 | if (!access) | |
1894 | return; | |
1895 | ||
1896 | if (ctx == ISRA_CTX_ARG) | |
1897 | { | |
1898 | gcc_checking_assert (call_info); | |
1899 | ||
1900 | if (!deref) | |
1901 | record_nonregister_call_use (desc, call_info, offset / BITS_PER_UNIT, | |
1902 | size / BITS_PER_UNIT); | |
1903 | else | |
1904 | /* This is not a pass-through of a pointer, this is a use like any | |
1905 | other. */ | |
1906 | access->nonarg = true; | |
1907 | } | |
10478270 MJ |
1908 | else if (ctx == ISRA_CTX_LOAD && bb->count.initialized_p ()) |
1909 | access->load_count += bb->count; | |
ff6686d2 MJ |
1910 | |
1911 | if (!access->type) | |
1912 | { | |
1913 | access->type = type; | |
1914 | access->alias_ptr_type = reference_alias_ptr_type (expr); | |
1915 | access->reverse = reverse; | |
1916 | } | |
1917 | else | |
1918 | { | |
1919 | if (exp_align < TYPE_ALIGN (access->type)) | |
1920 | { | |
1921 | disqualify_split_candidate (desc, "Reference has lower alignment " | |
1922 | "than a previous one."); | |
1923 | return; | |
1924 | } | |
1925 | if (access->alias_ptr_type != reference_alias_ptr_type (expr)) | |
1926 | { | |
1927 | disqualify_split_candidate (desc, "Multiple alias pointer types."); | |
1928 | return; | |
1929 | } | |
1930 | if (access->reverse != reverse) | |
1931 | { | |
1932 | disqualify_split_candidate (desc, "Both normal and reverse " | |
1933 | "scalar storage order."); | |
1934 | return; | |
1935 | } | |
1936 | if (!deref | |
1937 | && (AGGREGATE_TYPE_P (type) || AGGREGATE_TYPE_P (access->type)) | |
1938 | && (TYPE_MAIN_VARIANT (access->type) != TYPE_MAIN_VARIANT (type))) | |
1939 | { | |
1940 | /* We need the same aggregate type on all accesses to be able to | |
1941 | distinguish transformation spots from pass-through arguments in | |
dfea3d6f JJ |
1942 | the transformation phase. */ |
1943 | disqualify_split_candidate (desc, "We do not support aggregate " | |
ff6686d2 MJ |
1944 | "type punning."); |
1945 | return; | |
1946 | } | |
1947 | ||
1948 | if (type_prevails_p (access->type, type)) | |
1949 | access->type = type; | |
1950 | } | |
1951 | } | |
1952 | ||
1953 | /* Scan body function described by NODE and FUN and create access trees for | |
1954 | parameters. */ | |
1955 | ||
1956 | static void | |
1957 | scan_function (cgraph_node *node, struct function *fun) | |
1958 | { | |
1959 | basic_block bb; | |
1960 | ||
1961 | FOR_EACH_BB_FN (bb, fun) | |
1962 | { | |
1963 | gimple_stmt_iterator gsi; | |
1964 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1965 | { | |
1966 | gimple *stmt = gsi_stmt (gsi); | |
1967 | ||
e3a5cc32 | 1968 | if (final_bbs && stmt_can_throw_external (fun, stmt)) |
ff6686d2 MJ |
1969 | bitmap_set_bit (final_bbs, bb->index); |
1970 | switch (gimple_code (stmt)) | |
1971 | { | |
1972 | case GIMPLE_RETURN: | |
1973 | { | |
1974 | tree t = gimple_return_retval (as_a <greturn *> (stmt)); | |
1975 | if (t != NULL_TREE) | |
1976 | scan_expr_access (t, stmt, ISRA_CTX_LOAD, bb); | |
e3a5cc32 MJ |
1977 | if (final_bbs) |
1978 | bitmap_set_bit (final_bbs, bb->index); | |
ff6686d2 MJ |
1979 | } |
1980 | break; | |
1981 | ||
1982 | case GIMPLE_ASSIGN: | |
1983 | if (gimple_assign_single_p (stmt) | |
1984 | && !gimple_clobber_p (stmt)) | |
1985 | { | |
1986 | tree rhs = gimple_assign_rhs1 (stmt); | |
1987 | scan_expr_access (rhs, stmt, ISRA_CTX_LOAD, bb); | |
1988 | tree lhs = gimple_assign_lhs (stmt); | |
1989 | scan_expr_access (lhs, stmt, ISRA_CTX_STORE, bb); | |
1990 | } | |
1991 | break; | |
1992 | ||
1993 | case GIMPLE_CALL: | |
1994 | { | |
1995 | unsigned argument_count = gimple_call_num_args (stmt); | |
9707b593 MJ |
1996 | isra_scan_context ctx = ISRA_CTX_ARG; |
1997 | scan_call_info call_info, *call_info_p = &call_info; | |
1998 | if (gimple_call_internal_p (stmt)) | |
1999 | { | |
2000 | call_info_p = NULL; | |
2001 | ctx = ISRA_CTX_LOAD; | |
2002 | internal_fn ifn = gimple_call_internal_fn (stmt); | |
2003 | if (internal_store_fn_p (ifn)) | |
2004 | ctx = ISRA_CTX_STORE; | |
2005 | } | |
2006 | else | |
2007 | { | |
2008 | call_info.cs = node->get_edge (stmt); | |
2009 | call_info.argument_count = argument_count; | |
2010 | } | |
ff6686d2 MJ |
2011 | |
2012 | for (unsigned i = 0; i < argument_count; i++) | |
2013 | { | |
2014 | call_info.arg_idx = i; | |
2015 | scan_expr_access (gimple_call_arg (stmt, i), stmt, | |
9707b593 | 2016 | ctx, bb, call_info_p); |
ff6686d2 MJ |
2017 | } |
2018 | ||
2019 | tree lhs = gimple_call_lhs (stmt); | |
2020 | if (lhs) | |
2021 | scan_expr_access (lhs, stmt, ISRA_CTX_STORE, bb); | |
2022 | int flags = gimple_call_flags (stmt); | |
e3a5cc32 MJ |
2023 | if (final_bbs |
2024 | && (((flags & (ECF_CONST | ECF_PURE)) == 0) | |
2025 | || (flags & ECF_LOOPING_CONST_OR_PURE))) | |
ff6686d2 MJ |
2026 | bitmap_set_bit (final_bbs, bb->index); |
2027 | } | |
2028 | break; | |
2029 | ||
2030 | case GIMPLE_ASM: | |
2031 | { | |
2032 | gasm *asm_stmt = as_a <gasm *> (stmt); | |
2033 | walk_stmt_load_store_addr_ops (asm_stmt, NULL, NULL, NULL, | |
2034 | asm_visit_addr); | |
e3a5cc32 MJ |
2035 | if (final_bbs) |
2036 | bitmap_set_bit (final_bbs, bb->index); | |
ff6686d2 MJ |
2037 | |
2038 | for (unsigned i = 0; i < gimple_asm_ninputs (asm_stmt); i++) | |
2039 | { | |
2040 | tree t = TREE_VALUE (gimple_asm_input_op (asm_stmt, i)); | |
2041 | scan_expr_access (t, stmt, ISRA_CTX_LOAD, bb); | |
2042 | } | |
2043 | for (unsigned i = 0; i < gimple_asm_noutputs (asm_stmt); i++) | |
2044 | { | |
2045 | tree t = TREE_VALUE (gimple_asm_output_op (asm_stmt, i)); | |
2046 | scan_expr_access (t, stmt, ISRA_CTX_STORE, bb); | |
2047 | } | |
2048 | } | |
2049 | break; | |
2050 | ||
2051 | default: | |
2052 | break; | |
2053 | } | |
2054 | } | |
2055 | } | |
2056 | } | |
2057 | ||
9b8741c9 MJ |
2058 | /* Return true if SSA_NAME NAME of function described by FUN is only used in |
2059 | return statements, or if results of any operations it is involved in are | |
2060 | only used in return statements. ANALYZED is a bitmap that tracks which SSA | |
2061 | names we have already started investigating. */ | |
ff6686d2 MJ |
2062 | |
2063 | static bool | |
9b8741c9 | 2064 | ssa_name_only_returned_p (function *fun, tree name, bitmap analyzed) |
ff6686d2 MJ |
2065 | { |
2066 | bool res = true; | |
2067 | imm_use_iterator imm_iter; | |
2068 | gimple *stmt; | |
2069 | ||
2070 | FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name) | |
2071 | { | |
2072 | if (is_gimple_debug (stmt)) | |
2073 | continue; | |
2074 | ||
2075 | if (gimple_code (stmt) == GIMPLE_RETURN) | |
2076 | { | |
2077 | tree t = gimple_return_retval (as_a <greturn *> (stmt)); | |
2078 | if (t != name) | |
2079 | { | |
2080 | res = false; | |
640296c3 | 2081 | break; |
ff6686d2 MJ |
2082 | } |
2083 | } | |
9b8741c9 MJ |
2084 | else if (!stmt_unremovable_because_of_non_call_eh_p (fun, stmt) |
2085 | && ((is_gimple_assign (stmt) && !gimple_has_volatile_ops (stmt)) | |
2086 | || gimple_code (stmt) == GIMPLE_PHI)) | |
ff6686d2 MJ |
2087 | { |
2088 | /* TODO: And perhaps for const function calls too? */ | |
2089 | tree lhs; | |
2090 | if (gimple_code (stmt) == GIMPLE_PHI) | |
2091 | lhs = gimple_phi_result (stmt); | |
2092 | else | |
2093 | lhs = gimple_assign_lhs (stmt); | |
2094 | ||
2095 | if (TREE_CODE (lhs) != SSA_NAME) | |
2096 | { | |
2097 | res = false; | |
640296c3 | 2098 | break; |
ff6686d2 MJ |
2099 | } |
2100 | gcc_assert (!gimple_vdef (stmt)); | |
2101 | if (bitmap_set_bit (analyzed, SSA_NAME_VERSION (lhs)) | |
9b8741c9 | 2102 | && !ssa_name_only_returned_p (fun, lhs, analyzed)) |
ff6686d2 MJ |
2103 | { |
2104 | res = false; | |
640296c3 | 2105 | break; |
ff6686d2 MJ |
2106 | } |
2107 | } | |
2108 | else | |
2109 | { | |
2110 | res = false; | |
640296c3 | 2111 | break; |
ff6686d2 MJ |
2112 | } |
2113 | } | |
2114 | return res; | |
2115 | } | |
2116 | ||
2117 | /* Inspect the uses of the return value of the call associated with CS, and if | |
2118 | it is not used or if it is only used to construct the return value of the | |
2119 | caller, mark it as such in call or caller summary. Also check for | |
2120 | misaligned arguments. */ | |
2121 | ||
2122 | static void | |
2123 | isra_analyze_call (cgraph_edge *cs) | |
2124 | { | |
2125 | gcall *call_stmt = cs->call_stmt; | |
2126 | unsigned count = gimple_call_num_args (call_stmt); | |
2127 | isra_call_summary *csum = call_sums->get_create (cs); | |
2128 | ||
2129 | for (unsigned i = 0; i < count; i++) | |
2130 | { | |
2131 | tree arg = gimple_call_arg (call_stmt, i); | |
e3a5cc32 MJ |
2132 | if (TREE_CODE (arg) == ADDR_EXPR) |
2133 | { | |
2134 | poly_int64 poffset, psize, pmax_size; | |
2135 | bool reverse; | |
2136 | tree base = get_ref_base_and_extent (TREE_OPERAND (arg, 0), &poffset, | |
2137 | &psize, &pmax_size, &reverse); | |
f2cf4c61 MJ |
2138 | HOST_WIDE_INT offset; |
2139 | unsigned HOST_WIDE_INT ds; | |
2140 | if (DECL_P (base) | |
2141 | && (poffset.is_constant (&offset)) | |
2142 | && tree_fits_uhwi_p (DECL_SIZE (base)) | |
2143 | && ((ds = tree_to_uhwi (DECL_SIZE (base)) - offset) | |
2144 | < ISRA_ARG_SIZE_LIMIT * BITS_PER_UNIT)) | |
2145 | { | |
2146 | csum->init_inputs (count); | |
2147 | gcc_assert (!csum->m_arg_flow[i].aggregate_pass_through); | |
2148 | csum->m_arg_flow[i].unit_size = ds / BITS_PER_UNIT; | |
2149 | } | |
2150 | ||
e3a5cc32 MJ |
2151 | if (TREE_CODE (base) == VAR_DECL |
2152 | && !TREE_STATIC (base) | |
2153 | && !loaded_decls->contains (base)) | |
2154 | { | |
2155 | csum->init_inputs (count); | |
2156 | csum->m_arg_flow[i].constructed_for_calls = true; | |
2157 | } | |
2158 | } | |
2159 | ||
ff6686d2 MJ |
2160 | if (is_gimple_reg (arg)) |
2161 | continue; | |
2162 | ||
2163 | tree offset; | |
2164 | poly_int64 bitsize, bitpos; | |
2165 | machine_mode mode; | |
2166 | int unsignedp, reversep, volatilep = 0; | |
2167 | get_inner_reference (arg, &bitsize, &bitpos, &offset, &mode, | |
2168 | &unsignedp, &reversep, &volatilep); | |
2169 | if (!multiple_p (bitpos, BITS_PER_UNIT)) | |
2170 | { | |
2171 | csum->m_bit_aligned_arg = true; | |
2172 | break; | |
2173 | } | |
2174 | } | |
2175 | ||
2176 | tree lhs = gimple_call_lhs (call_stmt); | |
2177 | if (lhs) | |
2178 | { | |
2179 | /* TODO: Also detect aggregates on a LHS of a call that are only returned | |
2180 | from this function (without being read anywhere). */ | |
2181 | if (TREE_CODE (lhs) == SSA_NAME) | |
2182 | { | |
2183 | bitmap analyzed = BITMAP_ALLOC (NULL); | |
9b8741c9 MJ |
2184 | if (ssa_name_only_returned_p (DECL_STRUCT_FUNCTION (cs->caller->decl), |
2185 | lhs, analyzed)) | |
ff6686d2 MJ |
2186 | csum->m_return_returned = true; |
2187 | BITMAP_FREE (analyzed); | |
2188 | } | |
2189 | } | |
2190 | else | |
2191 | csum->m_return_ignored = true; | |
2192 | } | |
2193 | ||
2194 | /* Look at all calls going out of NODE, described also by IFS and perform all | |
2195 | analyses necessary for IPA-SRA that are not done at body scan time or done | |
2196 | even when body is not scanned because the function is not a candidate. */ | |
2197 | ||
2198 | static void | |
2199 | isra_analyze_all_outgoing_calls (cgraph_node *node) | |
2200 | { | |
2201 | for (cgraph_edge *cs = node->callees; cs; cs = cs->next_callee) | |
2202 | isra_analyze_call (cs); | |
2203 | for (cgraph_edge *cs = node->indirect_calls; cs; cs = cs->next_callee) | |
2204 | isra_analyze_call (cs); | |
2205 | } | |
2206 | ||
2207 | /* Dump a dereferences table with heading STR to file F. */ | |
2208 | ||
2209 | static void | |
2210 | dump_dereferences_table (FILE *f, struct function *fun, const char *str) | |
2211 | { | |
2212 | basic_block bb; | |
2213 | ||
2214 | fprintf (dump_file, "%s", str); | |
2215 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (fun), | |
2216 | EXIT_BLOCK_PTR_FOR_FN (fun), next_bb) | |
2217 | { | |
2218 | fprintf (f, "%4i %i ", bb->index, bitmap_bit_p (final_bbs, bb->index)); | |
2219 | if (bb != EXIT_BLOCK_PTR_FOR_FN (fun)) | |
2220 | { | |
2221 | int i; | |
10478270 | 2222 | for (i = 0; i < unsafe_by_ref_count; i++) |
ff6686d2 | 2223 | { |
10478270 | 2224 | int idx = bb->index * unsafe_by_ref_count + i; |
ff6686d2 MJ |
2225 | fprintf (f, " %4" HOST_WIDE_INT_PRINT "d", bb_dereferences[idx]); |
2226 | } | |
2227 | } | |
2228 | fprintf (f, "\n"); | |
2229 | } | |
2230 | fprintf (dump_file, "\n"); | |
2231 | } | |
2232 | ||
2233 | /* Propagate distances in bb_dereferences in the opposite direction than the | |
2234 | control flow edges, in each step storing the maximum of the current value | |
2235 | and the minimum of all successors. These steps are repeated until the table | |
2236 | stabilizes. Note that BBs which might terminate the functions (according to | |
2237 | final_bbs bitmap) never updated in this way. */ | |
2238 | ||
2239 | static void | |
2240 | propagate_dereference_distances (struct function *fun) | |
2241 | { | |
2242 | basic_block bb; | |
2243 | ||
2244 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2245 | dump_dereferences_table (dump_file, fun, | |
2246 | "Dereference table before propagation:\n"); | |
2247 | ||
2248 | auto_vec<basic_block> queue (last_basic_block_for_fn (fun)); | |
2249 | queue.quick_push (ENTRY_BLOCK_PTR_FOR_FN (fun)); | |
2250 | FOR_EACH_BB_FN (bb, fun) | |
2251 | { | |
2252 | queue.quick_push (bb); | |
2253 | bb->aux = bb; | |
2254 | } | |
2255 | ||
2256 | while (!queue.is_empty ()) | |
2257 | { | |
2258 | edge_iterator ei; | |
2259 | edge e; | |
2260 | bool change = false; | |
2261 | int i; | |
2262 | ||
2263 | bb = queue.pop (); | |
2264 | bb->aux = NULL; | |
2265 | ||
2266 | if (bitmap_bit_p (final_bbs, bb->index)) | |
2267 | continue; | |
2268 | ||
10478270 | 2269 | for (i = 0; i < unsafe_by_ref_count; i++) |
ff6686d2 | 2270 | { |
10478270 | 2271 | int idx = bb->index * unsafe_by_ref_count + i; |
ff6686d2 MJ |
2272 | bool first = true; |
2273 | HOST_WIDE_INT inh = 0; | |
2274 | ||
2275 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2276 | { | |
10478270 | 2277 | int succ_idx = e->dest->index * unsafe_by_ref_count + i; |
ff6686d2 MJ |
2278 | |
2279 | if (e->dest == EXIT_BLOCK_PTR_FOR_FN (fun)) | |
2280 | continue; | |
2281 | ||
2282 | if (first) | |
2283 | { | |
2284 | first = false; | |
2285 | inh = bb_dereferences [succ_idx]; | |
2286 | } | |
2287 | else if (bb_dereferences [succ_idx] < inh) | |
2288 | inh = bb_dereferences [succ_idx]; | |
2289 | } | |
2290 | ||
2291 | if (!first && bb_dereferences[idx] < inh) | |
2292 | { | |
2293 | bb_dereferences[idx] = inh; | |
2294 | change = true; | |
2295 | } | |
2296 | } | |
2297 | ||
2298 | if (change) | |
2299 | FOR_EACH_EDGE (e, ei, bb->preds) | |
2300 | { | |
2301 | if (e->src->aux) | |
2302 | continue; | |
2303 | ||
2304 | e->src->aux = e->src; | |
2305 | queue.quick_push (e->src); | |
2306 | } | |
2307 | } | |
2308 | ||
2309 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2310 | dump_dereferences_table (dump_file, fun, | |
2311 | "Dereference table after propagation:\n"); | |
2312 | } | |
2313 | ||
10478270 MJ |
2314 | /* Return true if the ACCESS loads happen frequently enough in FUN to risk |
2315 | moving them to the caller and only pass the result. */ | |
ff6686d2 MJ |
2316 | |
2317 | static bool | |
10478270 MJ |
2318 | dereference_probable_p (struct function *fun, gensum_param_access *access) |
2319 | { | |
2320 | int threshold = opt_for_fn (fun->decl, param_ipa_sra_deref_prob_threshold); | |
2321 | return access->load_count | |
2322 | >= ENTRY_BLOCK_PTR_FOR_FN (fun)->count.apply_scale (threshold, 100); | |
2323 | } | |
2324 | ||
2325 | /* Perform basic checks on ACCESS to PARM (of FUN) described by DESC and all | |
2326 | its children, return true if the parameter cannot be split, otherwise return | |
2327 | false and update *NONARG_ACC_SIZE and *ONLY_CALLS. ENTRY_BB_INDEX must be | |
2328 | the index of the entry BB in the function of PARM. */ | |
2329 | ||
2330 | static bool | |
2331 | check_gensum_access (struct function *fun, tree parm, gensum_param_desc *desc, | |
ff6686d2 MJ |
2332 | gensum_param_access *access, |
2333 | HOST_WIDE_INT *nonarg_acc_size, bool *only_calls, | |
c76b3bc5 | 2334 | int entry_bb_index) |
ff6686d2 MJ |
2335 | { |
2336 | if (access->nonarg) | |
2337 | { | |
2338 | *only_calls = false; | |
2339 | *nonarg_acc_size += access->size; | |
2340 | ||
2341 | if (access->first_child) | |
2342 | { | |
2343 | disqualify_split_candidate (desc, "Overlapping non-call uses."); | |
2344 | return true; | |
2345 | } | |
2346 | } | |
2347 | /* Do not decompose a non-BLKmode param in a way that would create | |
2348 | BLKmode params. Especially for by-reference passing (thus, | |
2349 | pointer-type param) this is hardly worthwhile. */ | |
2350 | if (DECL_MODE (parm) != BLKmode | |
2351 | && TYPE_MODE (access->type) == BLKmode) | |
2352 | { | |
2353 | disqualify_split_candidate (desc, "Would convert a non-BLK to a BLK."); | |
2354 | return true; | |
2355 | } | |
2356 | ||
2357 | if (desc->by_ref) | |
2358 | { | |
10478270 | 2359 | if (desc->safe_ref) |
ff6686d2 | 2360 | { |
10478270 MJ |
2361 | if (!dereference_probable_p (fun, access)) |
2362 | { | |
2363 | disqualify_split_candidate (desc, "Dereferences in callers " | |
2364 | "would happen much more frequently."); | |
2365 | return true; | |
2366 | } | |
2367 | } | |
2368 | else | |
2369 | { | |
2370 | int idx = (entry_bb_index * unsafe_by_ref_count + desc->deref_index); | |
2371 | if ((access->offset + access->size) > bb_dereferences[idx]) | |
2372 | { | |
f2cf4c61 MJ |
2373 | if (!dereference_probable_p (fun, access)) |
2374 | { | |
2375 | disqualify_split_candidate (desc, "Would create a possibly " | |
2376 | "illegal dereference in a " | |
2377 | "caller."); | |
2378 | return true; | |
2379 | } | |
2380 | desc->conditionally_dereferenceable = true; | |
10478270 | 2381 | } |
ff6686d2 MJ |
2382 | } |
2383 | } | |
2384 | ||
2385 | for (gensum_param_access *ch = access->first_child; | |
2386 | ch; | |
2387 | ch = ch->next_sibling) | |
10478270 | 2388 | if (check_gensum_access (fun, parm, desc, ch, nonarg_acc_size, only_calls, |
ff6686d2 MJ |
2389 | entry_bb_index)) |
2390 | return true; | |
2391 | ||
2392 | return false; | |
2393 | } | |
2394 | ||
2395 | /* Copy data from FROM and all of its children to a vector of accesses in IPA | |
2396 | descriptor DESC. */ | |
2397 | ||
2398 | static void | |
2399 | copy_accesses_to_ipa_desc (gensum_param_access *from, isra_param_desc *desc) | |
2400 | { | |
2401 | param_access *to = ggc_cleared_alloc<param_access> (); | |
2402 | gcc_checking_assert ((from->offset % BITS_PER_UNIT) == 0); | |
2403 | gcc_checking_assert ((from->size % BITS_PER_UNIT) == 0); | |
2404 | to->unit_offset = from->offset / BITS_PER_UNIT; | |
2405 | to->unit_size = from->size / BITS_PER_UNIT; | |
2406 | to->type = from->type; | |
2407 | to->alias_ptr_type = from->alias_ptr_type; | |
2408 | to->certain = from->nonarg; | |
2409 | to->reverse = from->reverse; | |
2410 | vec_safe_push (desc->accesses, to); | |
2411 | ||
2412 | for (gensum_param_access *ch = from->first_child; | |
2413 | ch; | |
2414 | ch = ch->next_sibling) | |
2415 | copy_accesses_to_ipa_desc (ch, desc); | |
2416 | } | |
2417 | ||
2418 | /* Analyze function body scan results stored in param_accesses and | |
2419 | param_accesses, detect possible transformations and store information of | |
2420 | those in function summary. NODE, FUN and IFS are all various structures | |
2421 | describing the currently analyzed function. */ | |
2422 | ||
2423 | static void | |
2424 | process_scan_results (cgraph_node *node, struct function *fun, | |
2425 | isra_func_summary *ifs, | |
2426 | vec<gensum_param_desc> *param_descriptions) | |
2427 | { | |
2428 | bool check_pass_throughs = false; | |
2429 | bool dereferences_propagated = false; | |
2430 | tree parm = DECL_ARGUMENTS (node->decl); | |
2431 | unsigned param_count = param_descriptions->length(); | |
2432 | ||
2433 | for (unsigned desc_index = 0; | |
2434 | desc_index < param_count; | |
2435 | desc_index++, parm = DECL_CHAIN (parm)) | |
2436 | { | |
2437 | gensum_param_desc *desc = &(*param_descriptions)[desc_index]; | |
581b519f | 2438 | if (!desc->split_candidate) |
ff6686d2 MJ |
2439 | continue; |
2440 | ||
2441 | if (flag_checking) | |
2442 | isra_verify_access_tree (desc->accesses); | |
2443 | ||
2444 | if (!dereferences_propagated | |
2445 | && desc->by_ref | |
10478270 | 2446 | && !desc->safe_ref |
ff6686d2 MJ |
2447 | && desc->accesses) |
2448 | { | |
2449 | propagate_dereference_distances (fun); | |
2450 | dereferences_propagated = true; | |
2451 | } | |
2452 | ||
2453 | HOST_WIDE_INT nonarg_acc_size = 0; | |
2454 | bool only_calls = true; | |
2455 | bool check_failed = false; | |
2456 | ||
2457 | int entry_bb_index = ENTRY_BLOCK_PTR_FOR_FN (fun)->index; | |
2458 | for (gensum_param_access *acc = desc->accesses; | |
2459 | acc; | |
2460 | acc = acc->next_sibling) | |
10478270 MJ |
2461 | if (check_gensum_access (fun, parm, desc, acc, &nonarg_acc_size, |
2462 | &only_calls, entry_bb_index)) | |
ff6686d2 MJ |
2463 | { |
2464 | check_failed = true; | |
2465 | break; | |
2466 | } | |
2467 | if (check_failed) | |
2468 | continue; | |
2469 | ||
2470 | if (only_calls) | |
2471 | desc->locally_unused = true; | |
2472 | ||
2473 | HOST_WIDE_INT cur_param_size | |
2474 | = tree_to_uhwi (TYPE_SIZE (TREE_TYPE (parm))); | |
e3a5cc32 | 2475 | HOST_WIDE_INT param_size_limit, optimistic_limit; |
ff6686d2 | 2476 | if (!desc->by_ref || optimize_function_for_size_p (fun)) |
e3a5cc32 MJ |
2477 | { |
2478 | param_size_limit = cur_param_size; | |
2479 | optimistic_limit = cur_param_size; | |
2480 | } | |
ff6686d2 | 2481 | else |
e3a5cc32 | 2482 | { |
fdfd7f53 ML |
2483 | param_size_limit |
2484 | = opt_for_fn (node->decl, | |
2485 | param_ipa_sra_ptr_growth_factor) * cur_param_size; | |
e3a5cc32 MJ |
2486 | optimistic_limit |
2487 | = (opt_for_fn (node->decl, param_ipa_sra_ptrwrap_growth_factor) | |
2488 | * param_size_limit); | |
2489 | } | |
2490 | ||
2491 | if (nonarg_acc_size > optimistic_limit | |
ff6686d2 MJ |
2492 | || (!desc->by_ref && nonarg_acc_size == param_size_limit)) |
2493 | { | |
f8cb8bcd | 2494 | disqualify_split_candidate (desc, "Would result into a too big set " |
e3a5cc32 MJ |
2495 | "of replacements even in best " |
2496 | "scenarios."); | |
ff6686d2 MJ |
2497 | } |
2498 | else | |
2499 | { | |
2500 | /* create_parameter_descriptors makes sure unit sizes of all | |
2501 | candidate parameters fit unsigned integers restricted to | |
2502 | ISRA_ARG_SIZE_LIMIT. */ | |
2503 | desc->param_size_limit = param_size_limit / BITS_PER_UNIT; | |
2504 | desc->nonarg_acc_size = nonarg_acc_size / BITS_PER_UNIT; | |
2505 | if (desc->split_candidate && desc->ptr_pt_count) | |
2506 | { | |
2507 | gcc_assert (desc->by_ref); | |
2508 | check_pass_throughs = true; | |
2509 | } | |
2510 | } | |
2511 | } | |
2512 | ||
2513 | /* When a pointer parameter is passed-through to a callee, in which it is | |
2514 | only used to read only one or a few items, we can attempt to transform it | |
2515 | to obtaining and passing through the items instead of the pointer. But we | |
2516 | must take extra care that 1) we do not introduce any segfault by moving | |
2517 | dereferences above control flow and that 2) the data is not modified | |
2518 | through an alias in this function. The IPA analysis must not introduce | |
2519 | any accesses candidates unless it can prove both. | |
2520 | ||
2521 | The current solution is very crude as it consists of ensuring that the | |
2522 | call postdominates entry BB and that the definition of VUSE of the call is | |
2523 | default definition. TODO: For non-recursive callees in the same | |
2524 | compilation unit we could do better by doing analysis in topological order | |
2525 | an looking into access candidates of callees, using their alias_ptr_types | |
2526 | to attempt real AA. We could also use the maximum known dereferenced | |
2527 | offset in this function at IPA level. | |
2528 | ||
2529 | TODO: Measure the overhead and the effect of just being pessimistic. | |
c76b3bc5 EB |
2530 | Maybe this is only -O3 material? */ |
2531 | ||
ff6686d2 MJ |
2532 | bool pdoms_calculated = false; |
2533 | if (check_pass_throughs) | |
2534 | for (cgraph_edge *cs = node->callees; cs; cs = cs->next_callee) | |
2535 | { | |
2536 | gcall *call_stmt = cs->call_stmt; | |
2537 | tree vuse = gimple_vuse (call_stmt); | |
2538 | ||
2539 | /* If the callee is a const function, we don't get a VUSE. In such | |
2540 | case there will be no memory accesses in the called function (or the | |
2541 | const attribute is wrong) and then we just don't care. */ | |
2542 | bool uses_memory_as_obtained = vuse && SSA_NAME_IS_DEFAULT_DEF (vuse); | |
2543 | ||
2544 | unsigned count = gimple_call_num_args (call_stmt); | |
2545 | isra_call_summary *csum = call_sums->get_create (cs); | |
2546 | csum->init_inputs (count); | |
763121cc | 2547 | csum->m_before_any_store = uses_memory_as_obtained; |
ff6686d2 MJ |
2548 | for (unsigned argidx = 0; argidx < count; argidx++) |
2549 | { | |
2550 | if (!csum->m_arg_flow[argidx].pointer_pass_through) | |
2551 | continue; | |
2552 | unsigned pidx | |
2553 | = get_single_param_flow_source (&csum->m_arg_flow[argidx]); | |
2554 | gensum_param_desc *desc = &(*param_descriptions)[pidx]; | |
2555 | if (!desc->split_candidate) | |
2556 | { | |
2557 | csum->m_arg_flow[argidx].pointer_pass_through = false; | |
2558 | continue; | |
2559 | } | |
2560 | if (!uses_memory_as_obtained) | |
2561 | continue; | |
2562 | ||
10478270 MJ |
2563 | if (desc->safe_ref) |
2564 | { | |
2565 | csum->m_arg_flow[argidx].safe_to_import_accesses = true; | |
2566 | continue; | |
2567 | } | |
2568 | ||
ff6686d2 MJ |
2569 | /* Post-dominator check placed last, hoping that it usually won't |
2570 | be needed. */ | |
2571 | if (!pdoms_calculated) | |
2572 | { | |
2573 | gcc_checking_assert (cfun); | |
ff6686d2 MJ |
2574 | connect_infinite_loops_to_exit (); |
2575 | calculate_dominance_info (CDI_POST_DOMINATORS); | |
2576 | pdoms_calculated = true; | |
2577 | } | |
2578 | if (dominated_by_p (CDI_POST_DOMINATORS, | |
2579 | gimple_bb (call_stmt), | |
2580 | single_succ (ENTRY_BLOCK_PTR_FOR_FN (fun)))) | |
2581 | csum->m_arg_flow[argidx].safe_to_import_accesses = true; | |
2582 | } | |
2583 | ||
2584 | } | |
2585 | if (pdoms_calculated) | |
2586 | { | |
2587 | free_dominance_info (CDI_POST_DOMINATORS); | |
2588 | remove_fake_exit_edges (); | |
2589 | } | |
2590 | ||
2591 | /* TODO: Add early exit if we disqualified everything. This also requires | |
2592 | that we either relax the restriction that | |
dfea3d6f | 2593 | ipa_param_adjustments.m_always_copy_start must be the number of PARM_DECLs |
ff6686d2 MJ |
2594 | or store the number of parameters to IPA-SRA function summary and use that |
2595 | when just removing params. */ | |
2596 | ||
2597 | vec_safe_reserve_exact (ifs->m_parameters, param_count); | |
2598 | ifs->m_parameters->quick_grow_cleared (param_count); | |
2599 | for (unsigned desc_index = 0; desc_index < param_count; desc_index++) | |
2600 | { | |
2601 | gensum_param_desc *s = &(*param_descriptions)[desc_index]; | |
2602 | isra_param_desc *d = &(*ifs->m_parameters)[desc_index]; | |
2603 | ||
2604 | d->param_size_limit = s->param_size_limit; | |
2605 | d->size_reached = s->nonarg_acc_size; | |
2606 | d->locally_unused = s->locally_unused; | |
2607 | d->split_candidate = s->split_candidate; | |
2608 | d->by_ref = s->by_ref; | |
f2cf4c61 | 2609 | d->conditionally_dereferenceable = s->conditionally_dereferenceable; |
ff6686d2 MJ |
2610 | |
2611 | for (gensum_param_access *acc = s->accesses; | |
2612 | acc; | |
2613 | acc = acc->next_sibling) | |
2614 | copy_accesses_to_ipa_desc (acc, d); | |
2615 | } | |
2616 | ||
2617 | if (dump_file) | |
e3a5cc32 | 2618 | dump_isra_param_descriptors (dump_file, node->decl, ifs, false); |
ff6686d2 MJ |
2619 | } |
2620 | ||
2621 | /* Return true if there are any overlaps among certain accesses of DESC. If | |
dfea3d6f | 2622 | non-NULL, set *CERTAIN_ACCESS_PRESENT_P upon encountering a certain access |
ff6686d2 MJ |
2623 | too. DESC is assumed to be a split candidate that is not locally |
2624 | unused. */ | |
2625 | ||
2626 | static bool | |
2627 | overlapping_certain_accesses_p (isra_param_desc *desc, | |
2628 | bool *certain_access_present_p) | |
2629 | { | |
2630 | unsigned pclen = vec_safe_length (desc->accesses); | |
2631 | for (unsigned i = 0; i < pclen; i++) | |
2632 | { | |
2633 | param_access *a1 = (*desc->accesses)[i]; | |
2634 | ||
2635 | if (!a1->certain) | |
2636 | continue; | |
2637 | if (certain_access_present_p) | |
2638 | *certain_access_present_p = true; | |
2639 | for (unsigned j = i + 1; j < pclen; j++) | |
2640 | { | |
2641 | param_access *a2 = (*desc->accesses)[j]; | |
2642 | if (a2->certain | |
2643 | && a1->unit_offset < a2->unit_offset + a2->unit_size | |
2644 | && a1->unit_offset + a1->unit_size > a2->unit_offset) | |
2645 | return true; | |
2646 | } | |
2647 | } | |
2648 | return false; | |
2649 | } | |
2650 | ||
2651 | /* Check for any overlaps of certain param accesses among splitting candidates | |
2652 | and signal an ICE if there are any. If CERTAIN_MUST_EXIST is set, also | |
2653 | check that used splitting candidates have at least one certain access. */ | |
2654 | ||
2655 | static void | |
2656 | verify_splitting_accesses (cgraph_node *node, bool certain_must_exist) | |
2657 | { | |
2658 | isra_func_summary *ifs = func_sums->get (node); | |
2659 | if (!ifs || !ifs->m_candidate) | |
2660 | return; | |
2661 | unsigned param_count = vec_safe_length (ifs->m_parameters); | |
2662 | for (unsigned pidx = 0; pidx < param_count; pidx++) | |
2663 | { | |
2664 | isra_param_desc *desc = &(*ifs->m_parameters)[pidx]; | |
2665 | if (!desc->split_candidate || desc->locally_unused) | |
2666 | continue; | |
2667 | ||
2668 | bool certain_access_present = !certain_must_exist; | |
2669 | if (overlapping_certain_accesses_p (desc, &certain_access_present)) | |
206222e0 | 2670 | internal_error ("function %qs, parameter %u, has IPA-SRA accesses " |
ff6686d2 MJ |
2671 | "which overlap", node->dump_name (), pidx); |
2672 | if (!certain_access_present) | |
206222e0 | 2673 | internal_error ("function %qs, parameter %u, is used but does not " |
ff6686d2 MJ |
2674 | "have any certain IPA-SRA access", |
2675 | node->dump_name (), pidx); | |
2676 | } | |
2677 | } | |
2678 | ||
ff6686d2 MJ |
2679 | /* Intraprocedural part of IPA-SRA analysis. Scan bodies of all functions in |
2680 | this compilation unit and create summary structures describing IPA-SRA | |
2681 | opportunities and constraints in them. */ | |
2682 | ||
2683 | static void | |
2684 | ipa_sra_generate_summary (void) | |
2685 | { | |
2686 | struct cgraph_node *node; | |
2687 | ||
2688 | gcc_checking_assert (!func_sums); | |
2689 | gcc_checking_assert (!call_sums); | |
2690 | func_sums | |
78cd68c0 | 2691 | = (new (ggc_alloc_no_dtor <ipa_sra_function_summaries> ()) |
ff6686d2 MJ |
2692 | ipa_sra_function_summaries (symtab, true)); |
2693 | call_sums = new ipa_sra_call_summaries (symtab); | |
2694 | ||
2695 | FOR_EACH_FUNCTION_WITH_GIMPLE_BODY (node) | |
2696 | ipa_sra_summarize_function (node); | |
2697 | return; | |
2698 | } | |
2699 | ||
dfea3d6f | 2700 | /* Write intraprocedural analysis information about E and all of its outgoing |
ff6686d2 MJ |
2701 | edges into a stream for LTO WPA. */ |
2702 | ||
2703 | static void | |
2704 | isra_write_edge_summary (output_block *ob, cgraph_edge *e) | |
2705 | { | |
2706 | isra_call_summary *csum = call_sums->get (e); | |
2707 | unsigned input_count = csum->m_arg_flow.length (); | |
2708 | streamer_write_uhwi (ob, input_count); | |
2709 | for (unsigned i = 0; i < input_count; i++) | |
2710 | { | |
2711 | isra_param_flow *ipf = &csum->m_arg_flow[i]; | |
2712 | streamer_write_hwi (ob, ipf->length); | |
2713 | bitpack_d bp = bitpack_create (ob->main_stream); | |
2714 | for (int j = 0; j < ipf->length; j++) | |
2715 | bp_pack_value (&bp, ipf->inputs[j], 8); | |
2716 | bp_pack_value (&bp, ipf->aggregate_pass_through, 1); | |
2717 | bp_pack_value (&bp, ipf->pointer_pass_through, 1); | |
2718 | bp_pack_value (&bp, ipf->safe_to_import_accesses, 1); | |
e3a5cc32 | 2719 | bp_pack_value (&bp, ipf->constructed_for_calls, 1); |
ff6686d2 MJ |
2720 | streamer_write_bitpack (&bp); |
2721 | streamer_write_uhwi (ob, ipf->unit_offset); | |
2722 | streamer_write_uhwi (ob, ipf->unit_size); | |
2723 | } | |
2724 | bitpack_d bp = bitpack_create (ob->main_stream); | |
2725 | bp_pack_value (&bp, csum->m_return_ignored, 1); | |
2726 | bp_pack_value (&bp, csum->m_return_returned, 1); | |
2727 | bp_pack_value (&bp, csum->m_bit_aligned_arg, 1); | |
763121cc | 2728 | bp_pack_value (&bp, csum->m_before_any_store, 1); |
ff6686d2 MJ |
2729 | streamer_write_bitpack (&bp); |
2730 | } | |
2731 | ||
dfea3d6f | 2732 | /* Write intraprocedural analysis information about NODE and all of its outgoing |
ff6686d2 MJ |
2733 | edges into a stream for LTO WPA. */ |
2734 | ||
2735 | static void | |
2736 | isra_write_node_summary (output_block *ob, cgraph_node *node) | |
2737 | { | |
2738 | isra_func_summary *ifs = func_sums->get (node); | |
2739 | lto_symtab_encoder_t encoder = ob->decl_state->symtab_node_encoder; | |
2740 | int node_ref = lto_symtab_encoder_encode (encoder, node); | |
2741 | streamer_write_uhwi (ob, node_ref); | |
2742 | ||
2743 | unsigned param_desc_count = vec_safe_length (ifs->m_parameters); | |
2744 | streamer_write_uhwi (ob, param_desc_count); | |
2745 | for (unsigned i = 0; i < param_desc_count; i++) | |
2746 | { | |
2747 | isra_param_desc *desc = &(*ifs->m_parameters)[i]; | |
2748 | unsigned access_count = vec_safe_length (desc->accesses); | |
2749 | streamer_write_uhwi (ob, access_count); | |
2750 | for (unsigned j = 0; j < access_count; j++) | |
2751 | { | |
2752 | param_access *acc = (*desc->accesses)[j]; | |
2753 | stream_write_tree (ob, acc->type, true); | |
2754 | stream_write_tree (ob, acc->alias_ptr_type, true); | |
2755 | streamer_write_uhwi (ob, acc->unit_offset); | |
2756 | streamer_write_uhwi (ob, acc->unit_size); | |
2757 | bitpack_d bp = bitpack_create (ob->main_stream); | |
2758 | bp_pack_value (&bp, acc->certain, 1); | |
c76b3bc5 | 2759 | bp_pack_value (&bp, acc->reverse, 1); |
ff6686d2 MJ |
2760 | streamer_write_bitpack (&bp); |
2761 | } | |
2762 | streamer_write_uhwi (ob, desc->param_size_limit); | |
2763 | streamer_write_uhwi (ob, desc->size_reached); | |
f2cf4c61 | 2764 | gcc_assert (desc->safe_size == 0); |
ff6686d2 MJ |
2765 | bitpack_d bp = bitpack_create (ob->main_stream); |
2766 | bp_pack_value (&bp, desc->locally_unused, 1); | |
2767 | bp_pack_value (&bp, desc->split_candidate, 1); | |
2768 | bp_pack_value (&bp, desc->by_ref, 1); | |
e3a5cc32 | 2769 | gcc_assert (!desc->not_specially_constructed); |
f2cf4c61 MJ |
2770 | bp_pack_value (&bp, desc->conditionally_dereferenceable, 1); |
2771 | gcc_assert (!desc->safe_size_set); | |
ff6686d2 MJ |
2772 | streamer_write_bitpack (&bp); |
2773 | } | |
2774 | bitpack_d bp = bitpack_create (ob->main_stream); | |
2775 | bp_pack_value (&bp, ifs->m_candidate, 1); | |
2776 | bp_pack_value (&bp, ifs->m_returns_value, 1); | |
2777 | bp_pack_value (&bp, ifs->m_return_ignored, 1); | |
2778 | gcc_assert (!ifs->m_queued); | |
2779 | streamer_write_bitpack (&bp); | |
2780 | ||
2781 | for (cgraph_edge *e = node->callees; e; e = e->next_callee) | |
2782 | isra_write_edge_summary (ob, e); | |
2783 | for (cgraph_edge *e = node->indirect_calls; e; e = e->next_callee) | |
2784 | isra_write_edge_summary (ob, e); | |
2785 | } | |
2786 | ||
dfea3d6f | 2787 | /* Write intraprocedural analysis information into a stream for LTO WPA. */ |
ff6686d2 MJ |
2788 | |
2789 | static void | |
2790 | ipa_sra_write_summary (void) | |
2791 | { | |
2792 | if (!func_sums || !call_sums) | |
2793 | return; | |
2794 | ||
2795 | struct output_block *ob = create_output_block (LTO_section_ipa_sra); | |
2796 | lto_symtab_encoder_t encoder = ob->decl_state->symtab_node_encoder; | |
2797 | ob->symbol = NULL; | |
2798 | ||
2799 | unsigned int count = 0; | |
2800 | lto_symtab_encoder_iterator lsei; | |
2801 | for (lsei = lsei_start_function_in_partition (encoder); | |
2802 | !lsei_end_p (lsei); | |
2803 | lsei_next_function_in_partition (&lsei)) | |
2804 | { | |
2805 | cgraph_node *node = lsei_cgraph_node (lsei); | |
2806 | if (node->has_gimple_body_p () | |
2807 | && func_sums->get (node) != NULL) | |
2808 | count++; | |
2809 | } | |
2810 | streamer_write_uhwi (ob, count); | |
2811 | ||
2812 | /* Process all of the functions. */ | |
2813 | for (lsei = lsei_start_function_in_partition (encoder); !lsei_end_p (lsei); | |
2814 | lsei_next_function_in_partition (&lsei)) | |
2815 | { | |
2816 | cgraph_node *node = lsei_cgraph_node (lsei); | |
2817 | if (node->has_gimple_body_p () | |
2818 | && func_sums->get (node) != NULL) | |
2819 | isra_write_node_summary (ob, node); | |
2820 | } | |
2821 | streamer_write_char_stream (ob->main_stream, 0); | |
2822 | produce_asm (ob, NULL); | |
2823 | destroy_output_block (ob); | |
2824 | } | |
2825 | ||
dfea3d6f | 2826 | /* Read intraprocedural analysis information about E and all of its outgoing |
ff6686d2 MJ |
2827 | edges into a stream for LTO WPA. */ |
2828 | ||
2829 | static void | |
2830 | isra_read_edge_summary (struct lto_input_block *ib, cgraph_edge *cs) | |
2831 | { | |
2832 | isra_call_summary *csum = call_sums->get_create (cs); | |
2833 | unsigned input_count = streamer_read_uhwi (ib); | |
2834 | csum->init_inputs (input_count); | |
2835 | for (unsigned i = 0; i < input_count; i++) | |
2836 | { | |
2837 | isra_param_flow *ipf = &csum->m_arg_flow[i]; | |
2838 | ipf->length = streamer_read_hwi (ib); | |
2839 | bitpack_d bp = streamer_read_bitpack (ib); | |
2840 | for (int j = 0; j < ipf->length; j++) | |
2841 | ipf->inputs[j] = bp_unpack_value (&bp, 8); | |
2842 | ipf->aggregate_pass_through = bp_unpack_value (&bp, 1); | |
2843 | ipf->pointer_pass_through = bp_unpack_value (&bp, 1); | |
2844 | ipf->safe_to_import_accesses = bp_unpack_value (&bp, 1); | |
e3a5cc32 | 2845 | ipf->constructed_for_calls = bp_unpack_value (&bp, 1); |
ff6686d2 MJ |
2846 | ipf->unit_offset = streamer_read_uhwi (ib); |
2847 | ipf->unit_size = streamer_read_uhwi (ib); | |
2848 | } | |
2849 | bitpack_d bp = streamer_read_bitpack (ib); | |
2850 | csum->m_return_ignored = bp_unpack_value (&bp, 1); | |
2851 | csum->m_return_returned = bp_unpack_value (&bp, 1); | |
2852 | csum->m_bit_aligned_arg = bp_unpack_value (&bp, 1); | |
763121cc | 2853 | csum->m_before_any_store = bp_unpack_value (&bp, 1); |
ff6686d2 MJ |
2854 | } |
2855 | ||
dfea3d6f | 2856 | /* Read intraprocedural analysis information about NODE and all of its outgoing |
ff6686d2 MJ |
2857 | edges into a stream for LTO WPA. */ |
2858 | ||
2859 | static void | |
2860 | isra_read_node_info (struct lto_input_block *ib, cgraph_node *node, | |
2861 | struct data_in *data_in) | |
2862 | { | |
2863 | isra_func_summary *ifs = func_sums->get_create (node); | |
2864 | unsigned param_desc_count = streamer_read_uhwi (ib); | |
2865 | if (param_desc_count > 0) | |
2866 | { | |
2867 | vec_safe_reserve_exact (ifs->m_parameters, param_desc_count); | |
2868 | ifs->m_parameters->quick_grow_cleared (param_desc_count); | |
2869 | } | |
2870 | for (unsigned i = 0; i < param_desc_count; i++) | |
2871 | { | |
2872 | isra_param_desc *desc = &(*ifs->m_parameters)[i]; | |
2873 | unsigned access_count = streamer_read_uhwi (ib); | |
2874 | for (unsigned j = 0; j < access_count; j++) | |
2875 | { | |
2876 | param_access *acc = ggc_cleared_alloc<param_access> (); | |
2877 | acc->type = stream_read_tree (ib, data_in); | |
2878 | acc->alias_ptr_type = stream_read_tree (ib, data_in); | |
2879 | acc->unit_offset = streamer_read_uhwi (ib); | |
2880 | acc->unit_size = streamer_read_uhwi (ib); | |
2881 | bitpack_d bp = streamer_read_bitpack (ib); | |
2882 | acc->certain = bp_unpack_value (&bp, 1); | |
c76b3bc5 | 2883 | acc->reverse = bp_unpack_value (&bp, 1); |
ff6686d2 MJ |
2884 | vec_safe_push (desc->accesses, acc); |
2885 | } | |
2886 | desc->param_size_limit = streamer_read_uhwi (ib); | |
2887 | desc->size_reached = streamer_read_uhwi (ib); | |
f2cf4c61 | 2888 | desc->safe_size = 0; |
ff6686d2 MJ |
2889 | bitpack_d bp = streamer_read_bitpack (ib); |
2890 | desc->locally_unused = bp_unpack_value (&bp, 1); | |
2891 | desc->split_candidate = bp_unpack_value (&bp, 1); | |
2892 | desc->by_ref = bp_unpack_value (&bp, 1); | |
e3a5cc32 | 2893 | desc->not_specially_constructed = 0; |
f2cf4c61 MJ |
2894 | desc->conditionally_dereferenceable = bp_unpack_value (&bp, 1); |
2895 | desc->safe_size_set = 0; | |
ff6686d2 MJ |
2896 | } |
2897 | bitpack_d bp = streamer_read_bitpack (ib); | |
2898 | ifs->m_candidate = bp_unpack_value (&bp, 1); | |
2899 | ifs->m_returns_value = bp_unpack_value (&bp, 1); | |
2900 | ifs->m_return_ignored = bp_unpack_value (&bp, 1); | |
2901 | ifs->m_queued = 0; | |
2902 | ||
2903 | for (cgraph_edge *e = node->callees; e; e = e->next_callee) | |
2904 | isra_read_edge_summary (ib, e); | |
2905 | for (cgraph_edge *e = node->indirect_calls; e; e = e->next_callee) | |
2906 | isra_read_edge_summary (ib, e); | |
2907 | } | |
2908 | ||
2909 | /* Read IPA-SRA summaries from a section in file FILE_DATA of length LEN with | |
e53b6e56 | 2910 | data DATA. TODO: This function was copied almost verbatim from ipa-prop.cc, |
ff6686d2 MJ |
2911 | it should be possible to unify them somehow. */ |
2912 | ||
2913 | static void | |
2914 | isra_read_summary_section (struct lto_file_decl_data *file_data, | |
2915 | const char *data, size_t len) | |
2916 | { | |
2917 | const struct lto_function_header *header = | |
2918 | (const struct lto_function_header *) data; | |
2919 | const int cfg_offset = sizeof (struct lto_function_header); | |
2920 | const int main_offset = cfg_offset + header->cfg_size; | |
2921 | const int string_offset = main_offset + header->main_size; | |
2922 | struct data_in *data_in; | |
2923 | unsigned int i; | |
2924 | unsigned int count; | |
2925 | ||
2926 | lto_input_block ib_main ((const char *) data + main_offset, | |
2927 | header->main_size, file_data->mode_table); | |
2928 | ||
2929 | data_in = | |
2930 | lto_data_in_create (file_data, (const char *) data + string_offset, | |
2931 | header->string_size, vNULL); | |
2932 | count = streamer_read_uhwi (&ib_main); | |
2933 | ||
2934 | for (i = 0; i < count; i++) | |
2935 | { | |
2936 | unsigned int index; | |
2937 | struct cgraph_node *node; | |
2938 | lto_symtab_encoder_t encoder; | |
2939 | ||
2940 | index = streamer_read_uhwi (&ib_main); | |
2941 | encoder = file_data->symtab_node_encoder; | |
2942 | node = dyn_cast<cgraph_node *> (lto_symtab_encoder_deref (encoder, | |
2943 | index)); | |
2944 | gcc_assert (node->definition); | |
2945 | isra_read_node_info (&ib_main, node, data_in); | |
2946 | } | |
2947 | lto_free_section_data (file_data, LTO_section_ipa_sra, NULL, data, | |
2948 | len); | |
2949 | lto_data_in_delete (data_in); | |
2950 | } | |
2951 | ||
dfea3d6f | 2952 | /* Read intraprocedural analysis information into a stream for LTO WPA. */ |
ff6686d2 MJ |
2953 | |
2954 | static void | |
2955 | ipa_sra_read_summary (void) | |
2956 | { | |
2957 | struct lto_file_decl_data **file_data_vec = lto_get_file_decl_data (); | |
2958 | struct lto_file_decl_data *file_data; | |
2959 | unsigned int j = 0; | |
2960 | ||
2961 | gcc_checking_assert (!func_sums); | |
2962 | gcc_checking_assert (!call_sums); | |
2963 | func_sums | |
78cd68c0 | 2964 | = (new (ggc_alloc_no_dtor <ipa_sra_function_summaries> ()) |
ff6686d2 MJ |
2965 | ipa_sra_function_summaries (symtab, true)); |
2966 | call_sums = new ipa_sra_call_summaries (symtab); | |
2967 | ||
2968 | while ((file_data = file_data_vec[j++])) | |
2969 | { | |
2970 | size_t len; | |
3c56d8d8 ML |
2971 | const char *data |
2972 | = lto_get_summary_section_data (file_data, LTO_section_ipa_sra, &len); | |
ff6686d2 MJ |
2973 | if (data) |
2974 | isra_read_summary_section (file_data, data, len); | |
2975 | } | |
2976 | } | |
2977 | ||
e3a5cc32 MJ |
2978 | /* Dump all IPA-SRA summary data for all cgraph nodes and edges to file F. If |
2979 | HINTS is true, also dump IPA-analysis computed hints. */ | |
ff6686d2 MJ |
2980 | |
2981 | static void | |
e3a5cc32 | 2982 | ipa_sra_dump_all_summaries (FILE *f, bool hints) |
ff6686d2 MJ |
2983 | { |
2984 | cgraph_node *node; | |
2985 | FOR_EACH_FUNCTION_WITH_GIMPLE_BODY (node) | |
2986 | { | |
2987 | fprintf (f, "\nSummary for node %s:\n", node->dump_name ()); | |
2988 | ||
2989 | isra_func_summary *ifs = func_sums->get (node); | |
2990 | if (!ifs) | |
717d278a MJ |
2991 | fprintf (f, " Function does not have any associated IPA-SRA " |
2992 | "summary\n"); | |
95489a2a MJ |
2993 | else if (!ifs->m_candidate) |
2994 | fprintf (f, " Not a candidate function\n"); | |
717d278a | 2995 | else |
ff6686d2 | 2996 | { |
717d278a MJ |
2997 | if (ifs->m_returns_value) |
2998 | fprintf (f, " Returns value\n"); | |
2999 | if (vec_safe_is_empty (ifs->m_parameters)) | |
3000 | fprintf (f, " No parameter information. \n"); | |
3001 | else | |
3002 | for (unsigned i = 0; i < ifs->m_parameters->length (); ++i) | |
3003 | { | |
3004 | fprintf (f, " Descriptor for parameter %i:\n", i); | |
e3a5cc32 | 3005 | dump_isra_param_descriptor (f, &(*ifs->m_parameters)[i], hints); |
717d278a MJ |
3006 | } |
3007 | fprintf (f, "\n"); | |
ff6686d2 | 3008 | } |
ff6686d2 MJ |
3009 | |
3010 | struct cgraph_edge *cs; | |
3011 | for (cs = node->callees; cs; cs = cs->next_callee) | |
3012 | { | |
3013 | fprintf (f, " Summary for edge %s->%s:\n", cs->caller->dump_name (), | |
3014 | cs->callee->dump_name ()); | |
3015 | isra_call_summary *csum = call_sums->get (cs); | |
3016 | if (csum) | |
3017 | csum->dump (f); | |
3018 | else | |
3019 | fprintf (f, " Call summary is MISSING!\n"); | |
3020 | } | |
3021 | ||
3022 | } | |
3023 | fprintf (f, "\n\n"); | |
3024 | } | |
3025 | ||
3026 | /* Perform function-scope viability tests that can be only made at IPA level | |
3027 | and return false if the function is deemed unsuitable for IPA-SRA. */ | |
3028 | ||
3029 | static bool | |
3030 | ipa_sra_ipa_function_checks (cgraph_node *node) | |
3031 | { | |
3032 | if (!node->can_be_local_p ()) | |
3033 | { | |
3034 | if (dump_file) | |
3035 | fprintf (dump_file, "Function %s disqualified because it cannot be " | |
3036 | "made local.\n", node->dump_name ()); | |
3037 | return false; | |
3038 | } | |
87f94429 | 3039 | if (!node->can_change_signature) |
ff6686d2 MJ |
3040 | { |
3041 | if (dump_file) | |
3042 | fprintf (dump_file, "Function can not change signature.\n"); | |
3043 | return false; | |
3044 | } | |
3045 | ||
3046 | return true; | |
3047 | } | |
3048 | ||
3049 | /* Issues found out by check_callers_for_issues. */ | |
3050 | ||
3051 | struct caller_issues | |
3052 | { | |
b90061c6 MJ |
3053 | /* The candidate being considered. */ |
3054 | cgraph_node *candidate; | |
ff6686d2 MJ |
3055 | /* There is a thunk among callers. */ |
3056 | bool thunk; | |
3057 | /* Call site with no available information. */ | |
3058 | bool unknown_callsite; | |
027e3041 | 3059 | /* Call from outside the candidate's comdat group. */ |
b90061c6 | 3060 | bool call_from_outside_comdat; |
ff6686d2 MJ |
3061 | /* There is a bit-aligned load into one of non-gimple-typed arguments. */ |
3062 | bool bit_aligned_aggregate_argument; | |
3063 | }; | |
3064 | ||
3065 | /* Worker for call_for_symbol_and_aliases, set any flags of passed caller_issues | |
3066 | that apply. */ | |
3067 | ||
3068 | static bool | |
3069 | check_for_caller_issues (struct cgraph_node *node, void *data) | |
3070 | { | |
3071 | struct caller_issues *issues = (struct caller_issues *) data; | |
3072 | ||
3073 | for (cgraph_edge *cs = node->callers; cs; cs = cs->next_caller) | |
3074 | { | |
67f3791f | 3075 | if (cs->caller->thunk) |
ff6686d2 MJ |
3076 | { |
3077 | issues->thunk = true; | |
3078 | /* TODO: We should be able to process at least some types of | |
3079 | thunks. */ | |
3080 | return true; | |
3081 | } | |
b90061c6 MJ |
3082 | if (issues->candidate->calls_comdat_local |
3083 | && issues->candidate->same_comdat_group | |
3084 | && !issues->candidate->in_same_comdat_group_p (cs->caller)) | |
3085 | { | |
3086 | issues->call_from_outside_comdat = true; | |
3087 | return true; | |
3088 | } | |
ff6686d2 MJ |
3089 | |
3090 | isra_call_summary *csum = call_sums->get (cs); | |
3091 | if (!csum) | |
3092 | { | |
3093 | issues->unknown_callsite = true; | |
3094 | return true; | |
3095 | } | |
3096 | ||
3097 | if (csum->m_bit_aligned_arg) | |
3098 | issues->bit_aligned_aggregate_argument = true; | |
3099 | } | |
3100 | return false; | |
3101 | } | |
3102 | ||
3103 | /* Look at all incoming edges to NODE, including aliases and thunks and look | |
3104 | for problems. Return true if NODE type should not be modified at all. */ | |
3105 | ||
3106 | static bool | |
3107 | check_all_callers_for_issues (cgraph_node *node) | |
3108 | { | |
3109 | struct caller_issues issues; | |
3110 | memset (&issues, 0, sizeof (issues)); | |
b90061c6 | 3111 | issues.candidate = node; |
ff6686d2 MJ |
3112 | |
3113 | node->call_for_symbol_and_aliases (check_for_caller_issues, &issues, true); | |
3114 | if (issues.unknown_callsite) | |
3115 | { | |
3116 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3117 | fprintf (dump_file, "A call of %s has not been analyzed. Disabling " | |
3118 | "all modifications.\n", node->dump_name ()); | |
3119 | return true; | |
3120 | } | |
3121 | /* TODO: We should be able to process at least some types of thunks. */ | |
3122 | if (issues.thunk) | |
3123 | { | |
3124 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3125 | fprintf (dump_file, "A call of %s is through thunk, which are not" | |
3126 | " handled yet. Disabling all modifications.\n", | |
3127 | node->dump_name ()); | |
3128 | return true; | |
3129 | } | |
b90061c6 MJ |
3130 | if (issues.call_from_outside_comdat) |
3131 | { | |
3132 | if (dump_file) | |
3133 | fprintf (dump_file, "Function would become private comdat called " | |
3134 | "outside of its comdat group.\n"); | |
3135 | return true; | |
3136 | } | |
ff6686d2 MJ |
3137 | |
3138 | if (issues.bit_aligned_aggregate_argument) | |
3139 | { | |
3140 | /* Let's only remove parameters/return values from such functions. | |
3141 | TODO: We could only prevent splitting the problematic parameters if | |
3142 | anybody thinks it is worth it. */ | |
3143 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
dfea3d6f | 3144 | fprintf (dump_file, "A call of %s has bit-aligned aggregate argument," |
ff6686d2 MJ |
3145 | " disabling parameter splitting.\n", node->dump_name ()); |
3146 | ||
3147 | isra_func_summary *ifs = func_sums->get (node); | |
3148 | gcc_checking_assert (ifs); | |
3149 | unsigned param_count = vec_safe_length (ifs->m_parameters); | |
3150 | for (unsigned i = 0; i < param_count; i++) | |
3151 | (*ifs->m_parameters)[i].split_candidate = false; | |
3152 | } | |
3153 | return false; | |
3154 | } | |
3155 | ||
3156 | /* Find the access with corresponding OFFSET and SIZE among accesses in | |
3157 | PARAM_DESC and return it or NULL if such an access is not there. */ | |
3158 | ||
3159 | static param_access * | |
3160 | find_param_access (isra_param_desc *param_desc, unsigned offset, unsigned size) | |
3161 | { | |
3162 | unsigned pclen = vec_safe_length (param_desc->accesses); | |
3163 | ||
3164 | /* The search is linear but the number of stored accesses is bound by | |
3165 | PARAM_IPA_SRA_MAX_REPLACEMENTS, so most probably 8. */ | |
3166 | ||
3167 | for (unsigned i = 0; i < pclen; i++) | |
3168 | if ((*param_desc->accesses)[i]->unit_offset == offset | |
3169 | && (*param_desc->accesses)[i]->unit_size == size) | |
3170 | return (*param_desc->accesses)[i]; | |
3171 | ||
3172 | return NULL; | |
3173 | } | |
3174 | ||
3175 | /* Return iff the total size of definite replacement SIZE would violate the | |
3176 | limit set for it in PARAM. */ | |
3177 | ||
3178 | static bool | |
3179 | size_would_violate_limit_p (isra_param_desc *desc, unsigned size) | |
3180 | { | |
3181 | unsigned limit = desc->param_size_limit; | |
3182 | if (size > limit | |
3183 | || (!desc->by_ref && size == limit)) | |
3184 | return true; | |
3185 | return false; | |
3186 | } | |
3187 | ||
3188 | /* Increase reached size of DESC by SIZE or disqualify it if it would violate | |
3189 | the set limit. IDX is the parameter number which is dumped when | |
3190 | disqualifying. */ | |
3191 | ||
3192 | static void | |
3193 | bump_reached_size (isra_param_desc *desc, unsigned size, unsigned idx) | |
3194 | { | |
3195 | unsigned after = desc->size_reached + size; | |
3196 | if (size_would_violate_limit_p (desc, after)) | |
3197 | { | |
3198 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3199 | fprintf (dump_file, " ...size limit reached, disqualifying " | |
3200 | "candidate parameter %u\n", idx); | |
3201 | desc->split_candidate = false; | |
3202 | return; | |
3203 | } | |
3204 | desc->size_reached = after; | |
3205 | } | |
3206 | ||
3207 | /* Take all actions required to deal with an edge CS that represents a call to | |
3208 | an unknown or un-analyzed function, for both parameter removal and | |
3209 | splitting. */ | |
3210 | ||
3211 | static void | |
3212 | process_edge_to_unknown_caller (cgraph_edge *cs) | |
3213 | { | |
3214 | isra_func_summary *from_ifs = func_sums->get (cs->caller); | |
3215 | gcc_checking_assert (from_ifs); | |
3216 | isra_call_summary *csum = call_sums->get (cs); | |
3217 | ||
3218 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3219 | fprintf (dump_file, "Processing an edge to an unknown caller from %s:\n", | |
3220 | cs->caller->dump_name ()); | |
3221 | ||
3222 | unsigned args_count = csum->m_arg_flow.length (); | |
3223 | for (unsigned i = 0; i < args_count; i++) | |
3224 | { | |
3225 | isra_param_flow *ipf = &csum->m_arg_flow[i]; | |
3226 | ||
3227 | if (ipf->pointer_pass_through) | |
3228 | { | |
3229 | isra_param_desc *param_desc | |
3230 | = &(*from_ifs->m_parameters)[get_single_param_flow_source (ipf)]; | |
3231 | param_desc->locally_unused = false; | |
3232 | param_desc->split_candidate = false; | |
3233 | continue; | |
3234 | } | |
3235 | if (ipf->aggregate_pass_through) | |
3236 | { | |
3237 | unsigned idx = get_single_param_flow_source (ipf); | |
3238 | isra_param_desc *param_desc = &(*from_ifs->m_parameters)[idx]; | |
3239 | ||
3240 | param_desc->locally_unused = false; | |
3241 | if (!param_desc->split_candidate) | |
3242 | continue; | |
3243 | gcc_assert (!param_desc->by_ref); | |
3244 | param_access *pacc = find_param_access (param_desc, ipf->unit_offset, | |
3245 | ipf->unit_size); | |
3246 | gcc_checking_assert (pacc); | |
3247 | pacc->certain = true; | |
3248 | if (overlapping_certain_accesses_p (param_desc, NULL)) | |
3249 | { | |
3250 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3251 | fprintf (dump_file, " ...leading to overlap, " | |
3252 | " disqualifying candidate parameter %u\n", | |
3253 | idx); | |
3254 | param_desc->split_candidate = false; | |
3255 | } | |
3256 | else | |
3257 | bump_reached_size (param_desc, pacc->unit_size, idx); | |
3258 | ipf->aggregate_pass_through = false; | |
3259 | continue; | |
3260 | } | |
3261 | ||
3262 | for (int j = 0; j < ipf->length; j++) | |
3263 | { | |
3264 | int input_idx = ipf->inputs[j]; | |
3265 | (*from_ifs->m_parameters)[input_idx].locally_unused = false; | |
3266 | } | |
3267 | } | |
3268 | } | |
3269 | ||
3270 | /* Propagate parameter removal information through cross-SCC edge CS, | |
3271 | i.e. decrease the use count in the caller parameter descriptor for each use | |
3272 | in this call. */ | |
3273 | ||
3274 | static void | |
3275 | param_removal_cross_scc_edge (cgraph_edge *cs) | |
3276 | { | |
3277 | enum availability availability; | |
3278 | cgraph_node *callee = cs->callee->function_symbol (&availability); | |
3279 | isra_func_summary *to_ifs = func_sums->get (callee); | |
3280 | if (!to_ifs || !to_ifs->m_candidate | |
3281 | || (availability < AVAIL_AVAILABLE) | |
3282 | || vec_safe_is_empty (to_ifs->m_parameters)) | |
3283 | { | |
3284 | process_edge_to_unknown_caller (cs); | |
3285 | return; | |
3286 | } | |
3287 | isra_func_summary *from_ifs = func_sums->get (cs->caller); | |
3288 | gcc_checking_assert (from_ifs); | |
3289 | ||
3290 | isra_call_summary *csum = call_sums->get (cs); | |
3291 | unsigned args_count = csum->m_arg_flow.length (); | |
3292 | unsigned param_count = vec_safe_length (to_ifs->m_parameters); | |
3293 | ||
3294 | for (unsigned i = 0; i < args_count; i++) | |
3295 | { | |
3296 | bool unused_in_callee; | |
3297 | if (i < param_count) | |
3298 | unused_in_callee = (*to_ifs->m_parameters)[i].locally_unused; | |
3299 | else | |
3300 | unused_in_callee = false; | |
3301 | ||
3302 | if (!unused_in_callee) | |
3303 | { | |
3304 | isra_param_flow *ipf = &csum->m_arg_flow[i]; | |
3305 | for (int j = 0; j < ipf->length; j++) | |
3306 | { | |
3307 | int input_idx = ipf->inputs[j]; | |
3308 | (*from_ifs->m_parameters)[input_idx].locally_unused = false; | |
3309 | } | |
3310 | } | |
3311 | } | |
3312 | } | |
3313 | ||
3314 | /* Unless it is already there, push NODE which is also described by IFS to | |
3315 | STACK. */ | |
3316 | ||
3317 | static void | |
3318 | isra_push_node_to_stack (cgraph_node *node, isra_func_summary *ifs, | |
3319 | vec<cgraph_node *> *stack) | |
3320 | { | |
3321 | if (!ifs->m_queued) | |
3322 | { | |
3323 | ifs->m_queued = true; | |
3324 | stack->safe_push (node); | |
3325 | } | |
3326 | } | |
3327 | ||
3328 | /* If parameter with index INPUT_IDX is marked as locally unused, mark it as | |
3329 | used and push CALLER on STACK. */ | |
3330 | ||
3331 | static void | |
3332 | isra_mark_caller_param_used (isra_func_summary *from_ifs, int input_idx, | |
3333 | cgraph_node *caller, vec<cgraph_node *> *stack) | |
3334 | { | |
3335 | if ((*from_ifs->m_parameters)[input_idx].locally_unused) | |
3336 | { | |
3337 | (*from_ifs->m_parameters)[input_idx].locally_unused = false; | |
3338 | isra_push_node_to_stack (caller, from_ifs, stack); | |
3339 | } | |
3340 | } | |
3341 | ||
f2cf4c61 | 3342 | /* Combine safe_size of DESC with SIZE and return true if it has changed. */ |
e3a5cc32 | 3343 | |
f2cf4c61 MJ |
3344 | static bool |
3345 | update_safe_size (isra_param_desc *desc, unsigned size) | |
3346 | { | |
3347 | if (!desc->safe_size_set) | |
3348 | { | |
3349 | desc->safe_size_set = 1; | |
3350 | desc->safe_size = size; | |
3351 | return true; | |
3352 | } | |
3353 | if (desc->safe_size <= size) | |
3354 | return false; | |
3355 | desc->safe_size = size; | |
3356 | return true; | |
3357 | } | |
3358 | ||
3359 | /* Set all param hints in DESC to the pessimistic values. Return true if any | |
3360 | hints that need to potentially trigger further propagation have changed. */ | |
3361 | ||
3362 | static bool | |
e3a5cc32 MJ |
3363 | flip_all_hints_pessimistic (isra_param_desc *desc) |
3364 | { | |
3365 | desc->not_specially_constructed = true; | |
f2cf4c61 | 3366 | return update_safe_size (desc, 0); |
e3a5cc32 MJ |
3367 | } |
3368 | ||
f2cf4c61 MJ |
3369 | /* Because we have not analyzed or otherwise problematic caller, go over all |
3370 | parameter int flags of IFS describing a call graph node of a calllee and | |
3371 | turn them pessimistic. Return true if any hints that need to potentially | |
3372 | trigger further propagation have changed. */ | |
e3a5cc32 | 3373 | |
f2cf4c61 MJ |
3374 | static bool |
3375 | flip_all_param_hints_pessimistic (isra_func_summary *ifs) | |
e3a5cc32 | 3376 | { |
e3a5cc32 | 3377 | if (!ifs || !ifs->m_candidate) |
f2cf4c61 | 3378 | return false; |
e3a5cc32 | 3379 | |
f2cf4c61 | 3380 | bool ret = false; |
e3a5cc32 MJ |
3381 | unsigned param_count = vec_safe_length (ifs->m_parameters); |
3382 | ||
3383 | for (unsigned i = 0; i < param_count; i++) | |
f2cf4c61 | 3384 | ret |= flip_all_hints_pessimistic (&(*ifs->m_parameters)[i]); |
e3a5cc32 | 3385 | |
f2cf4c61 | 3386 | return ret; |
e3a5cc32 MJ |
3387 | } |
3388 | ||
f2cf4c61 MJ |
3389 | /* Propagate hints accross edge CS which ultimately leads to a node described |
3390 | by TO_IFS. Return true if any hints of the callee which should potentially | |
3391 | trigger further propagation have changed. */ | |
e3a5cc32 | 3392 | |
f2cf4c61 MJ |
3393 | static bool |
3394 | propagate_param_hints_accross_call (cgraph_edge *cs, isra_func_summary *to_ifs) | |
e3a5cc32 | 3395 | { |
e3a5cc32 | 3396 | if (!to_ifs || !to_ifs->m_candidate) |
f2cf4c61 | 3397 | return false; |
e3a5cc32 | 3398 | |
f2cf4c61 MJ |
3399 | isra_call_summary *csum = call_sums->get (cs); |
3400 | bool ret = false; | |
e3a5cc32 MJ |
3401 | unsigned args_count = csum->m_arg_flow.length (); |
3402 | unsigned param_count = vec_safe_length (to_ifs->m_parameters); | |
3403 | ||
3404 | for (unsigned i = 0; i < param_count; i++) | |
3405 | { | |
3406 | isra_param_desc *desc = &(*to_ifs->m_parameters)[i]; | |
3407 | if (i >= args_count) | |
3408 | { | |
f2cf4c61 | 3409 | ret |= flip_all_hints_pessimistic (desc); |
e3a5cc32 MJ |
3410 | continue; |
3411 | } | |
3412 | ||
f2cf4c61 MJ |
3413 | if (desc->by_ref) |
3414 | { | |
3415 | isra_param_flow *ipf = &csum->m_arg_flow[i]; | |
3416 | ||
3417 | if (!ipf->constructed_for_calls) | |
3418 | desc->not_specially_constructed = true; | |
3419 | ||
3420 | if (ipf->pointer_pass_through) | |
3421 | { | |
3422 | isra_func_summary *from_ifs = func_sums->get (cs->caller); | |
3423 | int srcidx = get_single_param_flow_source (ipf); | |
3424 | if (vec_safe_length (from_ifs->m_parameters) > (unsigned) srcidx) | |
3425 | { | |
3426 | isra_param_desc *src_d = &(*from_ifs->m_parameters)[srcidx]; | |
3427 | if (src_d->safe_size_set) | |
3428 | ret |= update_safe_size (desc, src_d->safe_size); | |
3429 | } | |
3430 | else | |
3431 | ret |= update_safe_size (desc, 0); | |
3432 | } | |
3433 | else if (!ipf->aggregate_pass_through) | |
3434 | ret |= update_safe_size (desc, ipf->unit_size); | |
3435 | else | |
3436 | /* LTOing type-mismatched programs can end up here. */ | |
3437 | ret |= update_safe_size (desc, 0); | |
3438 | } | |
3439 | } | |
3440 | return ret; | |
3441 | } | |
3442 | ||
3443 | /* Propagate hints from NODE described by FROM_IFS to all its (dorect) callees, | |
3444 | push those that may need re-visiting onto STACK. */ | |
3445 | ||
3446 | static void | |
3447 | propagate_hints_to_all_callees (cgraph_node *node, isra_func_summary *from_ifs, | |
3448 | vec<cgraph_node *> *stack) | |
3449 | { | |
3450 | for (cgraph_edge *cs = node->callees; cs; cs = cs->next_callee) | |
3451 | { | |
3452 | enum availability availability; | |
3453 | cgraph_node *callee = cs->callee->function_symbol (&availability); | |
3454 | isra_func_summary *to_ifs = func_sums->get (callee); | |
3455 | if (!from_ifs) | |
3456 | { | |
3457 | if (flip_all_param_hints_pessimistic (to_ifs) | |
3458 | && ipa_edge_within_scc (cs)) | |
3459 | isra_push_node_to_stack (callee, to_ifs, stack); | |
3460 | } | |
3461 | else if (propagate_param_hints_accross_call (cs, to_ifs) | |
3462 | && ipa_edge_within_scc (cs)) | |
3463 | isra_push_node_to_stack (callee, to_ifs, stack); | |
e3a5cc32 | 3464 | } |
e3a5cc32 | 3465 | } |
ff6686d2 MJ |
3466 | |
3467 | /* Propagate information that any parameter is not used only locally within a | |
6b6a8065 | 3468 | SCC across CS to the caller, which must be in the same SCC as the |
c76b3bc5 | 3469 | callee. Push any callers that need to be re-processed to STACK. */ |
ff6686d2 MJ |
3470 | |
3471 | static void | |
3472 | propagate_used_across_scc_edge (cgraph_edge *cs, vec<cgraph_node *> *stack) | |
3473 | { | |
3474 | isra_func_summary *from_ifs = func_sums->get (cs->caller); | |
3475 | if (!from_ifs || vec_safe_is_empty (from_ifs->m_parameters)) | |
3476 | return; | |
3477 | ||
3478 | isra_call_summary *csum = call_sums->get (cs); | |
3479 | gcc_checking_assert (csum); | |
3480 | unsigned args_count = csum->m_arg_flow.length (); | |
3481 | enum availability availability; | |
3482 | cgraph_node *callee = cs->callee->function_symbol (&availability); | |
3483 | isra_func_summary *to_ifs = func_sums->get (callee); | |
3484 | ||
3485 | unsigned param_count | |
3486 | = (to_ifs && (availability >= AVAIL_AVAILABLE)) | |
3487 | ? vec_safe_length (to_ifs->m_parameters) : 0; | |
3488 | for (unsigned i = 0; i < args_count; i++) | |
3489 | { | |
3490 | if (i < param_count | |
3491 | && (*to_ifs->m_parameters)[i].locally_unused) | |
3492 | continue; | |
3493 | ||
3494 | /* The argument is needed in the callee it, we must mark the parameter as | |
3495 | used also in the caller and its callers within this SCC. */ | |
3496 | isra_param_flow *ipf = &csum->m_arg_flow[i]; | |
3497 | for (int j = 0; j < ipf->length; j++) | |
3498 | { | |
3499 | int input_idx = ipf->inputs[j]; | |
3500 | isra_mark_caller_param_used (from_ifs, input_idx, cs->caller, stack); | |
3501 | } | |
3502 | } | |
3503 | } | |
3504 | ||
3505 | /* Propagate information that any parameter is not used only locally within a | |
3506 | SCC (i.e. is used also elsewhere) to all callers of NODE that are in the | |
c76b3bc5 | 3507 | same SCC. Push any callers that need to be re-processed to STACK. */ |
ff6686d2 MJ |
3508 | |
3509 | static bool | |
3510 | propagate_used_to_scc_callers (cgraph_node *node, void *data) | |
3511 | { | |
3512 | vec<cgraph_node *> *stack = (vec<cgraph_node *> *) data; | |
3513 | cgraph_edge *cs; | |
3514 | for (cs = node->callers; cs; cs = cs->next_caller) | |
3515 | if (ipa_edge_within_scc (cs)) | |
3516 | propagate_used_across_scc_edge (cs, stack); | |
3517 | return false; | |
3518 | } | |
3519 | ||
3520 | /* Return true iff all certain accesses in ARG_DESC are also present as | |
3521 | certain accesses in PARAM_DESC. */ | |
3522 | ||
3523 | static bool | |
3524 | all_callee_accesses_present_p (isra_param_desc *param_desc, | |
3525 | isra_param_desc *arg_desc) | |
3526 | { | |
3527 | unsigned aclen = vec_safe_length (arg_desc->accesses); | |
3528 | for (unsigned j = 0; j < aclen; j++) | |
3529 | { | |
3530 | param_access *argacc = (*arg_desc->accesses)[j]; | |
3531 | if (!argacc->certain) | |
3532 | continue; | |
3533 | param_access *pacc = find_param_access (param_desc, argacc->unit_offset, | |
3534 | argacc->unit_size); | |
b9a15a83 MJ |
3535 | if (!pacc |
3536 | || !pacc->certain | |
3537 | || !types_compatible_p (argacc->type, pacc->type)) | |
ff6686d2 MJ |
3538 | return false; |
3539 | } | |
3540 | return true; | |
3541 | } | |
3542 | ||
3543 | /* Type internal to function pull_accesses_from_callee. Unfortunately gcc 4.8 | |
3544 | does not allow instantiating an auto_vec with a type defined within a | |
3545 | function so it is a global type. */ | |
3546 | enum acc_prop_kind {ACC_PROP_DONT, ACC_PROP_COPY, ACC_PROP_CERTAIN}; | |
3547 | ||
3548 | ||
1a315435 MJ |
3549 | /* Attempt to propagate all definite accesses from ARG_DESC to PARAM_DESC, |
3550 | (which belongs to CALLER) if they would not violate some constraint there. | |
3551 | If successful, return NULL, otherwise return the string reason for failure | |
3552 | (which can be written to the dump file). DELTA_OFFSET is the known offset | |
3553 | of the actual argument withing the formal parameter (so of ARG_DESCS within | |
3554 | PARAM_DESCS), ARG_SIZE is the size of the actual argument or zero, if not | |
3555 | known. In case of success, set *CHANGE_P to true if propagation actually | |
3556 | changed anything. */ | |
ff6686d2 MJ |
3557 | |
3558 | static const char * | |
1a315435 | 3559 | pull_accesses_from_callee (cgraph_node *caller, isra_param_desc *param_desc, |
ff6686d2 MJ |
3560 | isra_param_desc *arg_desc, |
3561 | unsigned delta_offset, unsigned arg_size, | |
3562 | bool *change_p) | |
3563 | { | |
3564 | unsigned pclen = vec_safe_length (param_desc->accesses); | |
3565 | unsigned aclen = vec_safe_length (arg_desc->accesses); | |
3566 | unsigned prop_count = 0; | |
3567 | unsigned prop_size = 0; | |
3568 | bool change = false; | |
3569 | ||
3570 | auto_vec <enum acc_prop_kind, 8> prop_kinds (aclen); | |
3571 | for (unsigned j = 0; j < aclen; j++) | |
3572 | { | |
3573 | param_access *argacc = (*arg_desc->accesses)[j]; | |
3574 | prop_kinds.safe_push (ACC_PROP_DONT); | |
3575 | ||
3576 | if (arg_size > 0 | |
3577 | && argacc->unit_offset + argacc->unit_size > arg_size) | |
3578 | return "callee access outsize size boundary"; | |
3579 | ||
3580 | if (!argacc->certain) | |
3581 | continue; | |
3582 | ||
3583 | unsigned offset = argacc->unit_offset + delta_offset; | |
3584 | /* Given that accesses are initially stored according to increasing | |
3585 | offset and decreasing size in case of equal offsets, the following | |
3586 | searches could be written more efficiently if we kept the ordering | |
3587 | when copying. But the number of accesses is capped at | |
3588 | PARAM_IPA_SRA_MAX_REPLACEMENTS (so most likely 8) and the code gets | |
3589 | messy quickly, so let's improve on that only if necessary. */ | |
3590 | ||
3591 | bool exact_match = false; | |
3592 | for (unsigned i = 0; i < pclen; i++) | |
3593 | { | |
3594 | /* Check for overlaps. */ | |
3595 | param_access *pacc = (*param_desc->accesses)[i]; | |
3596 | if (pacc->unit_offset == offset | |
3597 | && pacc->unit_size == argacc->unit_size) | |
3598 | { | |
3599 | if (argacc->alias_ptr_type != pacc->alias_ptr_type | |
c76b3bc5 EB |
3600 | || !types_compatible_p (argacc->type, pacc->type) |
3601 | || argacc->reverse != pacc->reverse) | |
ff6686d2 MJ |
3602 | return "propagated access types would not match existing ones"; |
3603 | ||
3604 | exact_match = true; | |
3605 | if (!pacc->certain) | |
3606 | { | |
3607 | prop_kinds[j] = ACC_PROP_CERTAIN; | |
3608 | prop_size += argacc->unit_size; | |
3609 | change = true; | |
3610 | } | |
3611 | continue; | |
3612 | } | |
3613 | ||
3614 | if (offset < pacc->unit_offset + pacc->unit_size | |
3615 | && offset + argacc->unit_size > pacc->unit_offset) | |
3616 | { | |
3617 | /* None permissible with load accesses, possible to fit into | |
3618 | argument ones. */ | |
3619 | if (pacc->certain | |
3620 | || offset < pacc->unit_offset | |
3621 | || (offset + argacc->unit_size | |
3622 | > pacc->unit_offset + pacc->unit_size)) | |
3623 | return "a propagated access would conflict in caller"; | |
3624 | } | |
3625 | } | |
3626 | ||
3627 | if (!exact_match) | |
3628 | { | |
3629 | prop_kinds[j] = ACC_PROP_COPY; | |
3630 | prop_count++; | |
3631 | prop_size += argacc->unit_size; | |
3632 | change = true; | |
3633 | } | |
3634 | } | |
3635 | ||
3636 | if (!change) | |
3637 | return NULL; | |
3638 | ||
3639 | if ((prop_count + pclen | |
1a315435 | 3640 | > (unsigned) opt_for_fn (caller->decl, param_ipa_sra_max_replacements)) |
ff6686d2 MJ |
3641 | || size_would_violate_limit_p (param_desc, |
3642 | param_desc->size_reached + prop_size)) | |
3643 | return "propagating accesses would violate the count or size limit"; | |
3644 | ||
3645 | *change_p = true; | |
3646 | for (unsigned j = 0; j < aclen; j++) | |
3647 | { | |
3648 | if (prop_kinds[j] == ACC_PROP_COPY) | |
3649 | { | |
3650 | param_access *argacc = (*arg_desc->accesses)[j]; | |
3651 | ||
3652 | param_access *copy = ggc_cleared_alloc<param_access> (); | |
3653 | copy->unit_offset = argacc->unit_offset + delta_offset; | |
3654 | copy->unit_size = argacc->unit_size; | |
3655 | copy->type = argacc->type; | |
3656 | copy->alias_ptr_type = argacc->alias_ptr_type; | |
3657 | copy->certain = true; | |
c76b3bc5 | 3658 | copy->reverse = argacc->reverse; |
ff6686d2 MJ |
3659 | vec_safe_push (param_desc->accesses, copy); |
3660 | } | |
3661 | else if (prop_kinds[j] == ACC_PROP_CERTAIN) | |
3662 | { | |
3663 | param_access *argacc = (*arg_desc->accesses)[j]; | |
3664 | param_access *csp | |
3665 | = find_param_access (param_desc, argacc->unit_offset + delta_offset, | |
3666 | argacc->unit_size); | |
3667 | csp->certain = true; | |
3668 | } | |
3669 | } | |
3670 | ||
3671 | param_desc->size_reached += prop_size; | |
3672 | ||
3673 | return NULL; | |
3674 | } | |
3675 | ||
3676 | /* Propagate parameter splitting information through call graph edge CS. | |
3677 | Return true if any changes that might need to be propagated within SCCs have | |
3678 | been made. The function also clears the aggregate_pass_through and | |
dfea3d6f | 3679 | pointer_pass_through in call summaries which do not need to be processed |
ff6686d2 MJ |
3680 | again if this CS is revisited when iterating while changes are propagated |
3681 | within an SCC. */ | |
3682 | ||
3683 | static bool | |
3684 | param_splitting_across_edge (cgraph_edge *cs) | |
3685 | { | |
3686 | bool res = false; | |
3687 | bool cross_scc = !ipa_edge_within_scc (cs); | |
3688 | enum availability availability; | |
3689 | cgraph_node *callee = cs->callee->function_symbol (&availability); | |
3690 | isra_func_summary *from_ifs = func_sums->get (cs->caller); | |
3691 | gcc_checking_assert (from_ifs && from_ifs->m_parameters); | |
3692 | ||
3693 | isra_call_summary *csum = call_sums->get (cs); | |
3694 | gcc_checking_assert (csum); | |
3695 | unsigned args_count = csum->m_arg_flow.length (); | |
3696 | isra_func_summary *to_ifs = func_sums->get (callee); | |
3697 | unsigned param_count | |
3698 | = ((to_ifs && to_ifs->m_candidate && (availability >= AVAIL_AVAILABLE)) | |
3699 | ? vec_safe_length (to_ifs->m_parameters) | |
3700 | : 0); | |
3701 | ||
3702 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
6b6a8065 | 3703 | fprintf (dump_file, "Splitting across %s->%s:\n", |
ff6686d2 MJ |
3704 | cs->caller->dump_name (), callee->dump_name ()); |
3705 | ||
3706 | unsigned i; | |
3707 | for (i = 0; (i < args_count) && (i < param_count); i++) | |
3708 | { | |
3709 | isra_param_desc *arg_desc = &(*to_ifs->m_parameters)[i]; | |
3710 | isra_param_flow *ipf = &csum->m_arg_flow[i]; | |
3711 | ||
3712 | if (arg_desc->locally_unused) | |
3713 | { | |
3714 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3715 | fprintf (dump_file, " ->%u: unused in callee\n", i); | |
3716 | ipf->pointer_pass_through = false; | |
3717 | continue; | |
3718 | } | |
3719 | ||
3720 | if (ipf->pointer_pass_through) | |
3721 | { | |
3722 | int idx = get_single_param_flow_source (ipf); | |
3723 | isra_param_desc *param_desc = &(*from_ifs->m_parameters)[idx]; | |
3724 | if (!param_desc->split_candidate) | |
3725 | continue; | |
3726 | gcc_assert (param_desc->by_ref); | |
3727 | ||
3728 | if (!arg_desc->split_candidate || !arg_desc->by_ref) | |
3729 | { | |
3730 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3731 | fprintf (dump_file, " %u->%u: not candidate or not by " | |
3732 | "reference in callee\n", idx, i); | |
3733 | param_desc->split_candidate = false; | |
3734 | ipf->pointer_pass_through = false; | |
3735 | res = true; | |
3736 | } | |
3737 | else if (!ipf->safe_to_import_accesses) | |
3738 | { | |
763121cc MJ |
3739 | if (!csum->m_before_any_store |
3740 | || !all_callee_accesses_present_p (param_desc, arg_desc)) | |
ff6686d2 MJ |
3741 | { |
3742 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3743 | fprintf (dump_file, " %u->%u: cannot import accesses.\n", | |
3744 | idx, i); | |
3745 | param_desc->split_candidate = false; | |
3746 | ipf->pointer_pass_through = false; | |
3747 | res = true; | |
3748 | ||
3749 | } | |
3750 | else | |
3751 | { | |
3752 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3753 | fprintf (dump_file, " %u->%u: verified callee accesses " | |
3754 | "present.\n", idx, i); | |
3755 | if (cross_scc) | |
3756 | ipf->pointer_pass_through = false; | |
3757 | } | |
3758 | } | |
3759 | else | |
3760 | { | |
3761 | const char *pull_failure | |
1a315435 MJ |
3762 | = pull_accesses_from_callee (cs->caller, param_desc, arg_desc, |
3763 | 0, 0, &res); | |
ff6686d2 MJ |
3764 | if (pull_failure) |
3765 | { | |
3766 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3767 | fprintf (dump_file, " %u->%u: by_ref access pull " | |
3768 | "failed: %s.\n", idx, i, pull_failure); | |
3769 | param_desc->split_candidate = false; | |
3770 | ipf->pointer_pass_through = false; | |
3771 | res = true; | |
3772 | } | |
3773 | else | |
3774 | { | |
3775 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3776 | fprintf (dump_file, " %u->%u: by_ref access pull " | |
3777 | "succeeded.\n", idx, i); | |
3778 | if (cross_scc) | |
3779 | ipf->pointer_pass_through = false; | |
3780 | } | |
3781 | } | |
3782 | } | |
3783 | else if (ipf->aggregate_pass_through) | |
3784 | { | |
3785 | int idx = get_single_param_flow_source (ipf); | |
3786 | isra_param_desc *param_desc = &(*from_ifs->m_parameters)[idx]; | |
3787 | if (!param_desc->split_candidate) | |
3788 | continue; | |
3789 | gcc_assert (!param_desc->by_ref); | |
3790 | param_access *pacc = find_param_access (param_desc, ipf->unit_offset, | |
3791 | ipf->unit_size); | |
3792 | gcc_checking_assert (pacc); | |
3793 | ||
3794 | if (pacc->certain) | |
3795 | { | |
3796 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3797 | fprintf (dump_file, " %u->%u: already certain\n", idx, i); | |
3798 | ipf->aggregate_pass_through = false; | |
3799 | } | |
3800 | else if (!arg_desc->split_candidate || arg_desc->by_ref) | |
3801 | { | |
3802 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3803 | fprintf (dump_file, " %u->%u: not candidate or by " | |
3804 | "reference in callee\n", idx, i); | |
3805 | ||
3806 | pacc->certain = true; | |
3807 | if (overlapping_certain_accesses_p (param_desc, NULL)) | |
3808 | { | |
3809 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3810 | fprintf (dump_file, " ...leading to overlap, " | |
3811 | " disqualifying candidate parameter %u\n", | |
3812 | idx); | |
3813 | param_desc->split_candidate = false; | |
3814 | } | |
3815 | else | |
3816 | bump_reached_size (param_desc, pacc->unit_size, idx); | |
3817 | ||
3818 | ipf->aggregate_pass_through = false; | |
3819 | res = true; | |
3820 | } | |
3821 | else | |
3822 | { | |
3823 | const char *pull_failure | |
1a315435 | 3824 | = pull_accesses_from_callee (cs->caller, param_desc, arg_desc, |
ff6686d2 MJ |
3825 | ipf->unit_offset, |
3826 | ipf->unit_size, &res); | |
3827 | if (pull_failure) | |
3828 | { | |
3829 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3830 | fprintf (dump_file, " %u->%u: arg access pull " | |
3831 | "failed: %s.\n", idx, i, pull_failure); | |
3832 | ||
3833 | ipf->aggregate_pass_through = false; | |
3834 | pacc->certain = true; | |
3835 | ||
3836 | if (overlapping_certain_accesses_p (param_desc, NULL)) | |
3837 | { | |
3838 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3839 | fprintf (dump_file, " ...leading to overlap, " | |
3840 | " disqualifying candidate parameter %u\n", | |
3841 | idx); | |
3842 | param_desc->split_candidate = false; | |
3843 | } | |
3844 | else | |
3845 | bump_reached_size (param_desc, pacc->unit_size, idx); | |
3846 | ||
3847 | res = true; | |
3848 | } | |
3849 | else | |
3850 | { | |
3851 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3852 | fprintf (dump_file, " %u->%u: arg access pull " | |
3853 | "succeeded.\n", idx, i); | |
3854 | if (cross_scc) | |
3855 | ipf->aggregate_pass_through = false; | |
3856 | } | |
3857 | } | |
3858 | } | |
3859 | } | |
3860 | ||
3861 | /* Handle argument-parameter count mismatches. */ | |
3862 | for (; (i < args_count); i++) | |
3863 | { | |
3864 | isra_param_flow *ipf = &csum->m_arg_flow[i]; | |
3865 | ||
3866 | if (ipf->pointer_pass_through || ipf->aggregate_pass_through) | |
3867 | { | |
3868 | int idx = get_single_param_flow_source (ipf); | |
3869 | ipf->pointer_pass_through = false; | |
3870 | ipf->aggregate_pass_through = false; | |
3871 | isra_param_desc *param_desc = &(*from_ifs->m_parameters)[idx]; | |
3872 | if (!param_desc->split_candidate) | |
3873 | continue; | |
3874 | ||
3875 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3876 | fprintf (dump_file, " %u->%u: no corresponding formal parameter\n", | |
3877 | idx, i); | |
3878 | param_desc->split_candidate = false; | |
3879 | res = true; | |
3880 | } | |
3881 | } | |
3882 | return res; | |
3883 | } | |
3884 | ||
3885 | /* Worker for call_for_symbol_and_aliases, look at all callers and if all their | |
3886 | callers ignore the return value, or come from the same SCC and use the | |
3887 | return value only to compute their return value, return false, otherwise | |
3888 | return true. */ | |
3889 | ||
3890 | static bool | |
3891 | retval_used_p (cgraph_node *node, void *) | |
3892 | { | |
3893 | for (cgraph_edge *cs = node->callers; cs; cs = cs->next_caller) | |
3894 | { | |
3895 | isra_call_summary *csum = call_sums->get (cs); | |
3896 | gcc_checking_assert (csum); | |
3897 | if (csum->m_return_ignored) | |
3898 | continue; | |
3899 | if (!csum->m_return_returned) | |
3900 | return true; | |
3901 | ||
3902 | isra_func_summary *from_ifs = func_sums->get (cs->caller); | |
3903 | if (!from_ifs || !from_ifs->m_candidate) | |
3904 | return true; | |
3905 | ||
3906 | if (!ipa_edge_within_scc (cs) | |
3907 | && !from_ifs->m_return_ignored) | |
3908 | return true; | |
3909 | } | |
3910 | ||
3911 | return false; | |
3912 | } | |
3913 | ||
3914 | /* Push into NEW_PARAMS all required parameter adjustment entries to copy or | |
3915 | modify parameter which originally had index BASE_INDEX, in the adjustment | |
3916 | vector of parent clone (if any) had PREV_CLONE_INDEX and was described by | |
4834e936 MJ |
3917 | PREV_ADJUSTMENT. If IPA-CP has created a transformation summary for the |
3918 | original node, it needs to be passed in IPCP_TS, otherwise it should be | |
3919 | NULL. If the parent clone is the original function, PREV_ADJUSTMENT is NULL | |
3920 | and PREV_CLONE_INDEX is equal to BASE_INDEX. */ | |
ff6686d2 | 3921 | |
ff6686d2 MJ |
3922 | static void |
3923 | push_param_adjustments_for_index (isra_func_summary *ifs, unsigned base_index, | |
3924 | unsigned prev_clone_index, | |
3925 | ipa_adjusted_param *prev_adjustment, | |
4834e936 | 3926 | ipcp_transformation *ipcp_ts, |
ff6686d2 MJ |
3927 | vec<ipa_adjusted_param, va_gc> **new_params) |
3928 | { | |
3929 | isra_param_desc *desc = &(*ifs->m_parameters)[base_index]; | |
3930 | if (desc->locally_unused) | |
3931 | { | |
3932 | if (dump_file) | |
3933 | fprintf (dump_file, " Will remove parameter %u\n", base_index); | |
3934 | return; | |
3935 | } | |
3936 | ||
3937 | if (!desc->split_candidate) | |
3938 | { | |
3939 | ipa_adjusted_param adj; | |
3940 | if (prev_adjustment) | |
3941 | { | |
3942 | adj = *prev_adjustment; | |
3943 | adj.prev_clone_adjustment = true; | |
3944 | adj.prev_clone_index = prev_clone_index; | |
3945 | } | |
3946 | else | |
3947 | { | |
3948 | memset (&adj, 0, sizeof (adj)); | |
3949 | adj.op = IPA_PARAM_OP_COPY; | |
3950 | adj.base_index = base_index; | |
3951 | adj.prev_clone_index = prev_clone_index; | |
3952 | } | |
3953 | vec_safe_push ((*new_params), adj); | |
3954 | return; | |
3955 | } | |
3956 | ||
3957 | if (dump_file) | |
3958 | fprintf (dump_file, " Will split parameter %u\n", base_index); | |
3959 | ||
3960 | gcc_assert (!prev_adjustment || prev_adjustment->op == IPA_PARAM_OP_COPY); | |
3961 | unsigned aclen = vec_safe_length (desc->accesses); | |
3962 | for (unsigned j = 0; j < aclen; j++) | |
3963 | { | |
3964 | param_access *pa = (*desc->accesses)[j]; | |
3965 | if (!pa->certain) | |
3966 | continue; | |
4834e936 MJ |
3967 | |
3968 | if (ipcp_ts) | |
3969 | { | |
3970 | ipa_argagg_value_list avl (ipcp_ts); | |
3971 | tree value = avl.get_value (base_index, pa->unit_offset); | |
3972 | if (value | |
3973 | && (tree_to_uhwi (TYPE_SIZE (TREE_TYPE (value))) / BITS_PER_UNIT | |
3974 | == pa->unit_size)) | |
3975 | { | |
3976 | if (dump_file) | |
3977 | fprintf (dump_file, " - omitting component at byte " | |
3978 | "offset %u which is known to have a constant value\n ", | |
3979 | pa->unit_offset); | |
3980 | continue; | |
3981 | } | |
3982 | } | |
3983 | ||
ff6686d2 MJ |
3984 | if (dump_file) |
3985 | fprintf (dump_file, " - component at byte offset %u, " | |
3986 | "size %u\n", pa->unit_offset, pa->unit_size); | |
3987 | ||
3988 | ipa_adjusted_param adj; | |
3989 | memset (&adj, 0, sizeof (adj)); | |
3990 | adj.op = IPA_PARAM_OP_SPLIT; | |
3991 | adj.base_index = base_index; | |
3992 | adj.prev_clone_index = prev_clone_index; | |
3993 | adj.param_prefix_index = IPA_PARAM_PREFIX_ISRA; | |
3994 | adj.reverse = pa->reverse; | |
3995 | adj.type = pa->type; | |
3996 | adj.alias_ptr_type = pa->alias_ptr_type; | |
3997 | adj.unit_offset = pa->unit_offset; | |
3998 | vec_safe_push ((*new_params), adj); | |
3999 | } | |
4000 | } | |
4001 | ||
b90061c6 MJ |
4002 | /* Worker for all call_for_symbol_thunks_and_aliases. Set calls_comdat_local |
4003 | flag of all callers of NODE. */ | |
4004 | ||
4005 | static bool | |
4006 | mark_callers_calls_comdat_local (struct cgraph_node *node, void *) | |
4007 | { | |
4008 | for (cgraph_edge *cs = node->callers; cs; cs = cs->next_caller) | |
4009 | cs->caller->calls_comdat_local = true; | |
4010 | return false; | |
4011 | } | |
4012 | ||
ff6686d2 | 4013 | |
dfea3d6f | 4014 | /* Do final processing of results of IPA propagation regarding NODE, clone it |
ff6686d2 MJ |
4015 | if appropriate. */ |
4016 | ||
4017 | static void | |
4018 | process_isra_node_results (cgraph_node *node, | |
4019 | hash_map<const char *, unsigned> *clone_num_suffixes) | |
4020 | { | |
4021 | isra_func_summary *ifs = func_sums->get (node); | |
4022 | if (!ifs || !ifs->m_candidate) | |
4023 | return; | |
4024 | ||
4025 | auto_vec<bool, 16> surviving_params; | |
4026 | bool check_surviving = false; | |
ae7a23a3 JH |
4027 | clone_info *cinfo = clone_info::get (node); |
4028 | if (cinfo && cinfo->param_adjustments) | |
ff6686d2 MJ |
4029 | { |
4030 | check_surviving = true; | |
ae7a23a3 | 4031 | cinfo->param_adjustments->get_surviving_params (&surviving_params); |
ff6686d2 MJ |
4032 | } |
4033 | ||
4034 | unsigned param_count = vec_safe_length (ifs->m_parameters); | |
4035 | bool will_change_function = false; | |
4036 | if (ifs->m_returns_value && ifs->m_return_ignored) | |
4037 | will_change_function = true; | |
4038 | else | |
4039 | for (unsigned i = 0; i < param_count; i++) | |
4040 | { | |
4041 | isra_param_desc *desc = &(*ifs->m_parameters)[i]; | |
4042 | if ((desc->locally_unused || desc->split_candidate) | |
4043 | /* Make sure we do not clone just to attempt to remove an already | |
4044 | removed unused argument. */ | |
4045 | && (!check_surviving | |
4046 | || (i < surviving_params.length () | |
4047 | && surviving_params[i]))) | |
4048 | { | |
4049 | will_change_function = true; | |
4050 | break; | |
4051 | } | |
4052 | } | |
4053 | if (!will_change_function) | |
4054 | return; | |
4055 | ||
4056 | if (dump_file) | |
4057 | { | |
4058 | fprintf (dump_file, "\nEvaluating analysis results for %s\n", | |
4059 | node->dump_name ()); | |
4060 | if (ifs->m_returns_value && ifs->m_return_ignored) | |
4061 | fprintf (dump_file, " Will remove return value.\n"); | |
4062 | } | |
4063 | ||
4834e936 | 4064 | ipcp_transformation *ipcp_ts = ipcp_get_transformation_summary (node); |
ff6686d2 | 4065 | vec<ipa_adjusted_param, va_gc> *new_params = NULL; |
ae7a23a3 JH |
4066 | if (ipa_param_adjustments *old_adjustments |
4067 | = cinfo ? cinfo->param_adjustments : NULL) | |
ff6686d2 MJ |
4068 | { |
4069 | unsigned old_adj_len = vec_safe_length (old_adjustments->m_adj_params); | |
4070 | for (unsigned i = 0; i < old_adj_len; i++) | |
4071 | { | |
4072 | ipa_adjusted_param *old_adj = &(*old_adjustments->m_adj_params)[i]; | |
4073 | push_param_adjustments_for_index (ifs, old_adj->base_index, i, | |
4834e936 | 4074 | old_adj, ipcp_ts, &new_params); |
ff6686d2 MJ |
4075 | } |
4076 | } | |
4077 | else | |
4078 | for (unsigned i = 0; i < param_count; i++) | |
4834e936 | 4079 | push_param_adjustments_for_index (ifs, i, i, NULL, ipcp_ts, &new_params); |
ff6686d2 MJ |
4080 | |
4081 | ipa_param_adjustments *new_adjustments | |
4082 | = (new (ggc_alloc <ipa_param_adjustments> ()) | |
4083 | ipa_param_adjustments (new_params, param_count, | |
4084 | ifs->m_returns_value && ifs->m_return_ignored)); | |
4085 | ||
4086 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4087 | { | |
4088 | fprintf (dump_file, "\n Created adjustments:\n"); | |
4089 | new_adjustments->dump (dump_file); | |
4090 | } | |
4091 | ||
4092 | unsigned &suffix_counter = clone_num_suffixes->get_or_insert ( | |
4093 | IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME ( | |
4094 | node->decl))); | |
265af872 | 4095 | auto_vec<cgraph_edge *> callers = node->collect_callers (); |
ff6686d2 MJ |
4096 | cgraph_node *new_node |
4097 | = node->create_virtual_clone (callers, NULL, new_adjustments, "isra", | |
4098 | suffix_counter); | |
4099 | suffix_counter++; | |
b90061c6 MJ |
4100 | if (node->calls_comdat_local && node->same_comdat_group) |
4101 | { | |
4102 | new_node->add_to_same_comdat_group (node); | |
4103 | new_node->call_for_symbol_and_aliases (mark_callers_calls_comdat_local, | |
4104 | NULL, true); | |
4105 | } | |
ed649cda | 4106 | new_node->calls_comdat_local = node->calls_comdat_local; |
ff6686d2 MJ |
4107 | |
4108 | if (dump_file) | |
4109 | fprintf (dump_file, " Created new node %s\n", new_node->dump_name ()); | |
4110 | callers.release (); | |
4111 | } | |
4112 | ||
4113 | /* Check which parameters of NODE described by IFS have survived until IPA-SRA | |
4114 | and disable transformations for those which have not or which should not | |
4115 | transformed because the associated debug counter reached its limit. Return | |
e3a5cc32 MJ |
4116 | true if none survived or if there were no candidates to begin with. |
4117 | Additionally, also adjust parameter descriptions based on debug counters and | |
4118 | hints propagated earlier. */ | |
ff6686d2 MJ |
4119 | |
4120 | static bool | |
e3a5cc32 | 4121 | adjust_parameter_descriptions (cgraph_node *node, isra_func_summary *ifs) |
ff6686d2 MJ |
4122 | { |
4123 | bool ret = true; | |
4124 | unsigned len = vec_safe_length (ifs->m_parameters); | |
4125 | if (!len) | |
4126 | return true; | |
4127 | ||
4128 | auto_vec<bool, 16> surviving_params; | |
4129 | bool check_surviving = false; | |
ae7a23a3 JH |
4130 | clone_info *cinfo = clone_info::get (node); |
4131 | if (cinfo && cinfo->param_adjustments) | |
ff6686d2 MJ |
4132 | { |
4133 | check_surviving = true; | |
ae7a23a3 | 4134 | cinfo->param_adjustments->get_surviving_params (&surviving_params); |
ff6686d2 | 4135 | } |
f2cf4c61 MJ |
4136 | auto_vec <unsigned> dump_dead_indices; |
4137 | auto_vec <unsigned> dump_bad_cond_indices; | |
ff6686d2 MJ |
4138 | for (unsigned i = 0; i < len; i++) |
4139 | { | |
4140 | isra_param_desc *desc = &(*ifs->m_parameters)[i]; | |
4141 | if (!dbg_cnt (ipa_sra_params)) | |
4142 | { | |
4143 | desc->locally_unused = false; | |
4144 | desc->split_candidate = false; | |
4145 | } | |
4146 | else if (check_surviving | |
4147 | && (i >= surviving_params.length () | |
4148 | || !surviving_params[i])) | |
4149 | { | |
4150 | /* Even if the parameter was removed by a previous IPA pass, we do | |
4151 | not clear locally_unused because if it really is unused, this | |
4152 | information might be useful in callers. */ | |
4153 | desc->split_candidate = false; | |
4154 | ||
4155 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
f2cf4c61 | 4156 | dump_dead_indices.safe_push (i); |
ff6686d2 | 4157 | } |
e3a5cc32 MJ |
4158 | else |
4159 | { | |
f2cf4c61 MJ |
4160 | if (desc->split_candidate && desc->conditionally_dereferenceable) |
4161 | { | |
4162 | gcc_assert (desc->safe_size_set); | |
4163 | for (param_access *pa : *desc->accesses) | |
4164 | if ((pa->unit_offset + pa->unit_size) > desc->safe_size) | |
4165 | { | |
4166 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4167 | dump_bad_cond_indices.safe_push (i); | |
4168 | desc->split_candidate = false; | |
4169 | break; | |
4170 | } | |
4171 | } | |
4172 | ||
e3a5cc32 MJ |
4173 | if (desc->split_candidate) |
4174 | { | |
4175 | if (desc->by_ref && !desc->not_specially_constructed) | |
4176 | { | |
4177 | int extra_factor | |
4178 | = opt_for_fn (node->decl, | |
4179 | param_ipa_sra_ptrwrap_growth_factor); | |
4180 | desc->param_size_limit = extra_factor * desc->param_size_limit; | |
4181 | } | |
4182 | if (size_would_violate_limit_p (desc, desc->size_reached)) | |
4183 | desc->split_candidate = false; | |
4184 | } | |
4185 | if (desc->locally_unused || desc->split_candidate) | |
4186 | ret = false; | |
4187 | } | |
ff6686d2 MJ |
4188 | } |
4189 | ||
f2cf4c61 MJ |
4190 | if (!dump_dead_indices.is_empty ()) |
4191 | { | |
4192 | fprintf (dump_file, "The following parameters of %s are dead on arrival:", | |
4193 | node->dump_name ()); | |
4194 | for (unsigned i : dump_dead_indices) | |
4195 | fprintf (dump_file, " %u", i); | |
4196 | fprintf (dump_file, "\n"); | |
4197 | } | |
4198 | if (!dump_bad_cond_indices.is_empty ()) | |
4199 | { | |
4200 | fprintf (dump_file, "The following parameters of %s are not safe to " | |
4201 | "derefernce in all callers:", node->dump_name ()); | |
4202 | for (unsigned i : dump_bad_cond_indices) | |
4203 | fprintf (dump_file, " %u", i); | |
4204 | fprintf (dump_file, "\n"); | |
4205 | } | |
ff6686d2 MJ |
4206 | |
4207 | return ret; | |
4208 | } | |
4209 | ||
4210 | ||
4211 | /* Run the interprocedural part of IPA-SRA. */ | |
4212 | ||
4213 | static unsigned int | |
4214 | ipa_sra_analysis (void) | |
4215 | { | |
4216 | if (dump_file) | |
4217 | { | |
4218 | fprintf (dump_file, "\n========== IPA-SRA IPA stage ==========\n"); | |
e3a5cc32 | 4219 | ipa_sra_dump_all_summaries (dump_file, false); |
ff6686d2 MJ |
4220 | } |
4221 | ||
4222 | gcc_checking_assert (func_sums); | |
4223 | gcc_checking_assert (call_sums); | |
4224 | cgraph_node **order = XCNEWVEC (cgraph_node *, symtab->cgraph_count); | |
4225 | auto_vec <cgraph_node *, 16> stack; | |
4226 | int node_scc_count = ipa_reduced_postorder (order, true, NULL); | |
4227 | ||
803a9133 MJ |
4228 | /* One sweep from callers to callees for return value removal. */ |
4229 | for (int i = node_scc_count - 1; i >= 0 ; i--) | |
ff6686d2 MJ |
4230 | { |
4231 | cgraph_node *scc_rep = order[i]; | |
4232 | vec<cgraph_node *> cycle_nodes = ipa_get_nodes_in_cycle (scc_rep); | |
ff6686d2 | 4233 | |
803a9133 MJ |
4234 | /* Preliminary IPA function level checks. */ |
4235 | for (cgraph_node *v : cycle_nodes) | |
ff6686d2 MJ |
4236 | { |
4237 | isra_func_summary *ifs = func_sums->get (v); | |
4238 | if (!ifs || !ifs->m_candidate) | |
4239 | continue; | |
4240 | if (!ipa_sra_ipa_function_checks (v) | |
4241 | || check_all_callers_for_issues (v)) | |
803a9133 MJ |
4242 | ifs->zap (); |
4243 | } | |
4244 | ||
4245 | for (cgraph_node *v : cycle_nodes) | |
4246 | { | |
4247 | isra_func_summary *ifs = func_sums->get (v); | |
4248 | if (!ifs || !ifs->m_candidate) | |
4249 | continue; | |
4250 | bool return_needed | |
4251 | = (ifs->m_returns_value | |
4252 | && (!dbg_cnt (ipa_sra_retvalues) | |
4253 | || v->call_for_symbol_and_aliases (retval_used_p, | |
4254 | NULL, true))); | |
4255 | ifs->m_return_ignored = !return_needed; | |
4256 | if (return_needed) | |
4257 | isra_push_node_to_stack (v, ifs, &stack); | |
4258 | } | |
4259 | ||
4260 | while (!stack.is_empty ()) | |
4261 | { | |
4262 | cgraph_node *node = stack.pop (); | |
4263 | isra_func_summary *ifs = func_sums->get (node); | |
4264 | gcc_checking_assert (ifs && ifs->m_queued); | |
4265 | ifs->m_queued = false; | |
4266 | ||
4267 | for (cgraph_edge *cs = node->callees; cs; cs = cs->next_callee) | |
4268 | if (ipa_edge_within_scc (cs) | |
4269 | && call_sums->get (cs)->m_return_returned) | |
4270 | { | |
4271 | enum availability av; | |
4272 | cgraph_node *callee = cs->callee->function_symbol (&av); | |
4273 | isra_func_summary *to_ifs = func_sums->get (callee); | |
4274 | if (to_ifs && to_ifs->m_return_ignored) | |
4275 | { | |
4276 | to_ifs->m_return_ignored = false; | |
4277 | isra_push_node_to_stack (callee, to_ifs, &stack); | |
4278 | } | |
4279 | } | |
4280 | } | |
e3a5cc32 MJ |
4281 | |
4282 | /* Parameter hint propagation. */ | |
4283 | for (cgraph_node *v : cycle_nodes) | |
4284 | { | |
4285 | isra_func_summary *ifs = func_sums->get (v); | |
f2cf4c61 MJ |
4286 | propagate_hints_to_all_callees (v, ifs, &stack); |
4287 | } | |
4288 | ||
4289 | while (!stack.is_empty ()) | |
4290 | { | |
4291 | cgraph_node *node = stack.pop (); | |
4292 | isra_func_summary *ifs = func_sums->get (node); | |
4293 | gcc_checking_assert (ifs && ifs->m_queued); | |
4294 | ifs->m_queued = false; | |
4295 | propagate_hints_to_all_callees (node, ifs, &stack); | |
e3a5cc32 MJ |
4296 | } |
4297 | ||
803a9133 MJ |
4298 | cycle_nodes.release (); |
4299 | } | |
4300 | ||
4301 | /* One sweep from callees to callers for parameter removal and splitting. */ | |
4302 | for (int i = 0; i < node_scc_count; i++) | |
4303 | { | |
4304 | cgraph_node *scc_rep = order[i]; | |
4305 | vec<cgraph_node *> cycle_nodes = ipa_get_nodes_in_cycle (scc_rep); | |
4306 | ||
4307 | /* First step of parameter removal. */ | |
4308 | for (cgraph_node *v : cycle_nodes) | |
4309 | { | |
4310 | isra_func_summary *ifs = func_sums->get (v); | |
4311 | if (!ifs || !ifs->m_candidate) | |
4312 | continue; | |
e3a5cc32 | 4313 | if (adjust_parameter_descriptions (v, ifs)) |
ff6686d2 MJ |
4314 | continue; |
4315 | for (cgraph_edge *cs = v->indirect_calls; cs; cs = cs->next_callee) | |
4316 | process_edge_to_unknown_caller (cs); | |
4317 | for (cgraph_edge *cs = v->callees; cs; cs = cs->next_callee) | |
4318 | if (!ipa_edge_within_scc (cs)) | |
4319 | param_removal_cross_scc_edge (cs); | |
4320 | } | |
4321 | ||
6b6a8065 JJ |
4322 | /* Look at edges within the current SCC and propagate used-ness across |
4323 | them, pushing onto the stack all notes which might need to be | |
4324 | revisited. */ | |
803a9133 | 4325 | for (cgraph_node *v : cycle_nodes) |
ff6686d2 MJ |
4326 | v->call_for_symbol_thunks_and_aliases (propagate_used_to_scc_callers, |
4327 | &stack, true); | |
4328 | ||
4329 | /* Keep revisiting and pushing until nothing changes. */ | |
4330 | while (!stack.is_empty ()) | |
4331 | { | |
4332 | cgraph_node *v = stack.pop (); | |
4333 | isra_func_summary *ifs = func_sums->get (v); | |
4334 | gcc_checking_assert (ifs && ifs->m_queued); | |
4335 | ifs->m_queued = false; | |
4336 | ||
4337 | v->call_for_symbol_thunks_and_aliases (propagate_used_to_scc_callers, | |
4338 | &stack, true); | |
4339 | } | |
4340 | ||
4341 | /* Parameter splitting. */ | |
4342 | bool repeat_scc_access_propagation; | |
4343 | do | |
4344 | { | |
4345 | repeat_scc_access_propagation = false; | |
803a9133 | 4346 | for (cgraph_node *v : cycle_nodes) |
ff6686d2 MJ |
4347 | { |
4348 | isra_func_summary *ifs = func_sums->get (v); | |
4349 | if (!ifs | |
4350 | || !ifs->m_candidate | |
4351 | || vec_safe_is_empty (ifs->m_parameters)) | |
4352 | continue; | |
4353 | for (cgraph_edge *cs = v->callees; cs; cs = cs->next_callee) | |
4354 | if (param_splitting_across_edge (cs)) | |
4355 | repeat_scc_access_propagation = true; | |
4356 | } | |
4357 | } | |
4358 | while (repeat_scc_access_propagation); | |
4359 | ||
4360 | if (flag_checking) | |
803a9133 | 4361 | for (cgraph_node *v : cycle_nodes) |
ff6686d2 MJ |
4362 | verify_splitting_accesses (v, true); |
4363 | ||
4364 | cycle_nodes.release (); | |
4365 | } | |
4366 | ||
ff6686d2 MJ |
4367 | ipa_free_postorder_info (); |
4368 | free (order); | |
4369 | ||
4370 | if (dump_file) | |
4371 | { | |
4372 | if (dump_flags & TDF_DETAILS) | |
4373 | { | |
4374 | fprintf (dump_file, "\n========== IPA-SRA propagation final state " | |
4375 | " ==========\n"); | |
e3a5cc32 | 4376 | ipa_sra_dump_all_summaries (dump_file, true); |
ff6686d2 MJ |
4377 | } |
4378 | fprintf (dump_file, "\n========== IPA-SRA decisions ==========\n"); | |
4379 | } | |
4380 | ||
4381 | hash_map<const char *, unsigned> *clone_num_suffixes | |
4382 | = new hash_map<const char *, unsigned>; | |
4383 | ||
4384 | cgraph_node *node; | |
4385 | FOR_EACH_FUNCTION_WITH_GIMPLE_BODY (node) | |
4386 | process_isra_node_results (node, clone_num_suffixes); | |
4387 | ||
4388 | delete clone_num_suffixes; | |
ddf628e4 | 4389 | ggc_delete (func_sums); |
ff6686d2 | 4390 | func_sums = NULL; |
78cd68c0 | 4391 | delete call_sums; |
ff6686d2 MJ |
4392 | call_sums = NULL; |
4393 | ||
4394 | if (dump_file) | |
4395 | fprintf (dump_file, "\n========== IPA SRA IPA analysis done " | |
4396 | "==========\n\n"); | |
4397 | return 0; | |
4398 | } | |
4399 | ||
4400 | ||
4401 | const pass_data pass_data_ipa_sra = | |
4402 | { | |
4403 | IPA_PASS, /* type */ | |
4404 | "sra", /* name */ | |
4405 | OPTGROUP_NONE, /* optinfo_flags */ | |
4406 | TV_IPA_SRA, /* tv_id */ | |
4407 | 0, /* properties_required */ | |
4408 | 0, /* properties_provided */ | |
4409 | 0, /* properties_destroyed */ | |
4410 | 0, /* todo_flags_start */ | |
4411 | ( TODO_dump_symtab | TODO_remove_functions ), /* todo_flags_finish */ | |
4412 | }; | |
4413 | ||
4414 | class pass_ipa_sra : public ipa_opt_pass_d | |
4415 | { | |
4416 | public: | |
4417 | pass_ipa_sra (gcc::context *ctxt) | |
4418 | : ipa_opt_pass_d (pass_data_ipa_sra, ctxt, | |
4419 | ipa_sra_generate_summary, /* generate_summary */ | |
4420 | ipa_sra_write_summary, /* write_summary */ | |
4421 | ipa_sra_read_summary, /* read_summary */ | |
4422 | NULL , /* write_optimization_summary */ | |
4423 | NULL, /* read_optimization_summary */ | |
4424 | NULL, /* stmt_fixup */ | |
4425 | 0, /* function_transform_todo_flags_start */ | |
4426 | NULL, /* function_transform */ | |
4427 | NULL) /* variable_transform */ | |
4428 | {} | |
4429 | ||
4430 | /* opt_pass methods: */ | |
725793af | 4431 | bool gate (function *) final override |
ff6686d2 MJ |
4432 | { |
4433 | /* TODO: We should remove the optimize check after we ensure we never run | |
4434 | IPA passes when not optimizing. */ | |
4435 | return (flag_ipa_sra && optimize); | |
4436 | } | |
4437 | ||
725793af DM |
4438 | unsigned int execute (function *) final override |
4439 | { | |
4440 | return ipa_sra_analysis (); | |
4441 | } | |
ff6686d2 MJ |
4442 | |
4443 | }; // class pass_ipa_sra | |
4444 | ||
4445 | } // anon namespace | |
4446 | ||
40e67ab8 JH |
4447 | /* Intraprocedural part of IPA-SRA analysis. Scan function body of NODE and |
4448 | create a summary structure describing IPA-SRA opportunities and constraints | |
4449 | in it. */ | |
4450 | ||
4451 | static void | |
4452 | ipa_sra_summarize_function (cgraph_node *node) | |
4453 | { | |
4454 | if (dump_file) | |
4455 | fprintf (dump_file, "Creating summary for %s/%i:\n", node->name (), | |
4456 | node->order); | |
40e67ab8 | 4457 | gcc_obstack_init (&gensum_obstack); |
e3a5cc32 | 4458 | loaded_decls = new hash_set<tree>; |
40e67ab8 | 4459 | |
e3a5cc32 | 4460 | isra_func_summary *ifs = NULL; |
40e67ab8 | 4461 | unsigned count = 0; |
e3a5cc32 MJ |
4462 | if (ipa_sra_preliminary_function_checks (node)) |
4463 | { | |
4464 | ifs = func_sums->get_create (node); | |
4465 | ifs->m_candidate = true; | |
4466 | tree ret = TREE_TYPE (TREE_TYPE (node->decl)); | |
4467 | ifs->m_returns_value = (TREE_CODE (ret) != VOID_TYPE); | |
4468 | for (tree parm = DECL_ARGUMENTS (node->decl); | |
4469 | parm; | |
4470 | parm = DECL_CHAIN (parm)) | |
4471 | count++; | |
4472 | } | |
4473 | auto_vec<gensum_param_desc, 16> param_descriptions (count); | |
40e67ab8 | 4474 | |
e3a5cc32 MJ |
4475 | struct function *fun = DECL_STRUCT_FUNCTION (node->decl); |
4476 | bool cfun_pushed = false; | |
40e67ab8 JH |
4477 | if (count > 0) |
4478 | { | |
e3a5cc32 | 4479 | decl2desc = new hash_map<tree, gensum_param_desc *>; |
40e67ab8 JH |
4480 | param_descriptions.reserve_exact (count); |
4481 | param_descriptions.quick_grow_cleared (count); | |
4482 | ||
40e67ab8 JH |
4483 | if (create_parameter_descriptors (node, ¶m_descriptions)) |
4484 | { | |
4485 | push_cfun (fun); | |
4486 | cfun_pushed = true; | |
4487 | final_bbs = BITMAP_ALLOC (NULL); | |
4488 | bb_dereferences = XCNEWVEC (HOST_WIDE_INT, | |
10478270 | 4489 | unsafe_by_ref_count |
40e67ab8 JH |
4490 | * last_basic_block_for_fn (fun)); |
4491 | aa_walking_limit = opt_for_fn (node->decl, param_ipa_max_aa_steps); | |
e3a5cc32 MJ |
4492 | } |
4493 | } | |
4494 | /* Scan function is run even when there are no removal or splitting | |
4495 | candidates so that we can calculate hints on call edges which can be | |
4496 | useful in callees. */ | |
4497 | scan_function (node, fun); | |
40e67ab8 | 4498 | |
e3a5cc32 MJ |
4499 | if (count > 0) |
4500 | { | |
4501 | if (dump_file) | |
4502 | { | |
4503 | dump_gensum_param_descriptors (dump_file, node->decl, | |
4504 | ¶m_descriptions); | |
4505 | fprintf (dump_file, "----------------------------------------\n"); | |
40e67ab8 | 4506 | } |
e3a5cc32 | 4507 | |
40e67ab8 JH |
4508 | process_scan_results (node, fun, ifs, ¶m_descriptions); |
4509 | ||
4510 | if (cfun_pushed) | |
4511 | pop_cfun (); | |
4512 | if (bb_dereferences) | |
4513 | { | |
4514 | free (bb_dereferences); | |
4515 | bb_dereferences = NULL; | |
4516 | BITMAP_FREE (final_bbs); | |
4517 | final_bbs = NULL; | |
4518 | } | |
4519 | } | |
4520 | isra_analyze_all_outgoing_calls (node); | |
4521 | ||
e3a5cc32 MJ |
4522 | delete loaded_decls; |
4523 | loaded_decls = NULL; | |
4524 | if (decl2desc) | |
4525 | { | |
4526 | delete decl2desc; | |
4527 | decl2desc = NULL; | |
4528 | } | |
40e67ab8 JH |
4529 | obstack_free (&gensum_obstack, NULL); |
4530 | if (dump_file) | |
4531 | fprintf (dump_file, "\n\n"); | |
4532 | if (flag_checking) | |
4533 | verify_splitting_accesses (node, false); | |
4534 | return; | |
4535 | } | |
4536 | ||
ff6686d2 MJ |
4537 | ipa_opt_pass_d * |
4538 | make_pass_ipa_sra (gcc::context *ctxt) | |
4539 | { | |
4540 | return new pass_ipa_sra (ctxt); | |
4541 | } | |
4542 | ||
4543 | ||
4544 | #include "gt-ipa-sra.h" |