Mercurial > hg > truffle
annotate src/share/vm/c1/c1_ValueMap.cpp @ 17467:55fb97c4c58d hs25-b65
8029233: Update copyright year to match last edit in jdk8 hotspot repository for 2013
Summary: Copyright year updated for files modified during 2013
Reviewed-by: twisti, iveresov
| author | mikael |
|---|---|
| date | Tue, 24 Dec 2013 11:48:39 -0800 |
| parents | 84ab5667f290 |
| children | 4ca6dc0799b6 |
| rev | line source |
|---|---|
| 0 | 1 /* |
|
17467
55fb97c4c58d
8029233: Update copyright year to match last edit in jdk8 hotspot repository for 2013
mikael
parents:
9081
diff
changeset
|
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved. |
| 0 | 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 * | |
| 5 * This code is free software; you can redistribute it and/or modify it | |
| 6 * under the terms of the GNU General Public License version 2 only, as | |
| 7 * published by the Free Software Foundation. | |
| 8 * | |
| 9 * This code is distributed in the hope that it will be useful, but WITHOUT | |
| 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 12 * version 2 for more details (a copy is included in the LICENSE file that | |
| 13 * accompanied this code). | |
| 14 * | |
| 15 * You should have received a copy of the GNU General Public License version | |
| 16 * 2 along with this work; if not, write to the Free Software Foundation, | |
| 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| 18 * | |
|
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
0
diff
changeset
|
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
|
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
0
diff
changeset
|
20 * or visit www.oracle.com if you need additional information or have any |
|
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
0
diff
changeset
|
21 * questions. |
| 0 | 22 * |
| 23 */ | |
| 24 | |
| 1972 | 25 #include "precompiled.hpp" |
| 26 #include "c1/c1_Canonicalizer.hpp" | |
| 27 #include "c1/c1_IR.hpp" | |
| 28 #include "c1/c1_ValueMap.hpp" | |
| 8860 | 29 #include "c1/c1_ValueStack.hpp" |
| 1972 | 30 #include "utilities/bitMap.inline.hpp" |
| 0 | 31 |
| 32 #ifndef PRODUCT | |
| 33 | |
| 34 int ValueMap::_number_of_finds = 0; | |
| 35 int ValueMap::_number_of_hits = 0; | |
| 36 int ValueMap::_number_of_kills = 0; | |
| 37 | |
| 38 #define TRACE_VALUE_NUMBERING(code) if (PrintValueNumbering) { code; } | |
| 39 | |
| 40 #else | |
| 41 | |
| 42 #define TRACE_VALUE_NUMBERING(code) | |
| 43 | |
| 44 #endif | |
| 45 | |
| 46 | |
| 47 ValueMap::ValueMap() | |
| 48 : _nesting(0) | |
| 49 , _entries(ValueMapInitialSize, NULL) | |
| 50 , _killed_values() | |
| 51 , _entry_count(0) | |
| 52 { | |
| 53 NOT_PRODUCT(reset_statistics()); | |
| 54 } | |
| 55 | |
| 56 | |
| 57 ValueMap::ValueMap(ValueMap* old) | |
| 58 : _nesting(old->_nesting + 1) | |
| 59 , _entries(old->_entries.length()) | |
| 60 , _killed_values() | |
| 61 , _entry_count(old->_entry_count) | |
| 62 { | |
| 63 for (int i = size() - 1; i >= 0; i--) { | |
| 64 _entries.at_put(i, old->entry_at(i)); | |
| 65 } | |
| 66 _killed_values.set_from(&old->_killed_values); | |
| 67 } | |
| 68 | |
| 69 | |
| 70 void ValueMap::increase_table_size() { | |
| 71 int old_size = size(); | |
| 72 int new_size = old_size * 2 + 1; | |
| 73 | |
| 74 ValueMapEntryList worklist(8); | |
| 75 ValueMapEntryArray new_entries(new_size, NULL); | |
| 76 int new_entry_count = 0; | |
| 77 | |
| 78 TRACE_VALUE_NUMBERING(tty->print_cr("increasing table size from %d to %d", old_size, new_size)); | |
| 79 | |
| 80 for (int i = old_size - 1; i >= 0; i--) { | |
| 81 ValueMapEntry* entry; | |
| 82 for (entry = entry_at(i); entry != NULL; entry = entry->next()) { | |
| 83 if (!is_killed(entry->value())) { | |
| 84 worklist.push(entry); | |
| 85 } | |
| 86 } | |
| 87 | |
| 88 while (!worklist.is_empty()) { | |
| 89 entry = worklist.pop(); | |
| 90 int new_index = entry_index(entry->hash(), new_size); | |
| 91 | |
| 92 if (entry->nesting() != nesting() && new_entries.at(new_index) != entry->next()) { | |
| 93 // changing entries with a lower nesting than the current nesting of the table | |
| 94 // is not allowed because then the same entry is contained in multiple value maps. | |
| 95 // clone entry when next-pointer must be changed | |
| 96 entry = new ValueMapEntry(entry->hash(), entry->value(), entry->nesting(), NULL); | |
| 97 } | |
| 98 entry->set_next(new_entries.at(new_index)); | |
| 99 new_entries.at_put(new_index, entry); | |
| 100 new_entry_count++; | |
| 101 } | |
| 102 } | |
| 103 | |
| 104 _entries = new_entries; | |
| 105 _entry_count = new_entry_count; | |
| 106 } | |
| 107 | |
| 108 | |
| 109 Value ValueMap::find_insert(Value x) { | |
| 110 const intx hash = x->hash(); | |
| 111 if (hash != 0) { | |
| 112 // 0 hash means: exclude from value numbering | |
| 113 NOT_PRODUCT(_number_of_finds++); | |
| 114 | |
| 115 for (ValueMapEntry* entry = entry_at(entry_index(hash, size())); entry != NULL; entry = entry->next()) { | |
| 116 if (entry->hash() == hash) { | |
| 117 Value f = entry->value(); | |
| 118 | |
| 119 if (!is_killed(f) && f->is_equal(x)) { | |
| 120 NOT_PRODUCT(_number_of_hits++); | |
| 121 TRACE_VALUE_NUMBERING(tty->print_cr("Value Numbering: %s %c%d equal to %c%d (size %d, entries %d, nesting-diff %d)", x->name(), x->type()->tchar(), x->id(), f->type()->tchar(), f->id(), size(), entry_count(), nesting() - entry->nesting())); | |
| 122 | |
| 123 if (entry->nesting() != nesting() && f->as_Constant() == NULL) { | |
| 124 // non-constant values of of another block must be pinned, | |
| 125 // otherwise it is possible that they are not evaluated | |
| 126 f->pin(Instruction::PinGlobalValueNumbering); | |
| 127 } | |
|
4871
f067b4e0e04b
7090976: Eclipse/CDT causes a JVM crash while indexing C++ code
roland
parents:
1972
diff
changeset
|
128 assert(x->type()->tag() == f->type()->tag(), "should have same type"); |
| 0 | 129 |
| 130 return f; | |
| 131 | |
| 132 } | |
| 133 } | |
| 134 } | |
| 135 | |
| 136 // x not found, so insert it | |
| 137 if (entry_count() >= size_threshold()) { | |
| 138 increase_table_size(); | |
| 139 } | |
| 140 int idx = entry_index(hash, size()); | |
| 141 _entries.at_put(idx, new ValueMapEntry(hash, x, nesting(), entry_at(idx))); | |
| 142 _entry_count++; | |
| 143 | |
| 144 TRACE_VALUE_NUMBERING(tty->print_cr("Value Numbering: insert %s %c%d (size %d, entries %d, nesting %d)", x->name(), x->type()->tchar(), x->id(), size(), entry_count(), nesting())); | |
| 145 } | |
| 146 | |
| 147 return x; | |
| 148 } | |
| 149 | |
| 150 | |
| 151 #define GENERIC_KILL_VALUE(must_kill_implementation) \ | |
| 152 NOT_PRODUCT(_number_of_kills++); \ | |
| 153 \ | |
| 154 for (int i = size() - 1; i >= 0; i--) { \ | |
| 155 ValueMapEntry* prev_entry = NULL; \ | |
| 156 for (ValueMapEntry* entry = entry_at(i); entry != NULL; entry = entry->next()) { \ | |
| 157 Value value = entry->value(); \ | |
| 158 \ | |
| 159 must_kill_implementation(must_kill, entry, value) \ | |
| 160 \ | |
| 161 if (must_kill) { \ | |
| 162 kill_value(value); \ | |
| 163 \ | |
| 164 if (prev_entry == NULL) { \ | |
| 165 _entries.at_put(i, entry->next()); \ | |
| 166 _entry_count--; \ | |
| 167 } else if (prev_entry->nesting() == nesting()) { \ | |
| 168 prev_entry->set_next(entry->next()); \ | |
| 169 _entry_count--; \ | |
| 170 } else { \ | |
| 171 prev_entry = entry; \ | |
| 172 } \ | |
| 173 \ | |
| 174 TRACE_VALUE_NUMBERING(tty->print_cr("Value Numbering: killed %s %c%d (size %d, entries %d, nesting-diff %d)", value->name(), value->type()->tchar(), value->id(), size(), entry_count(), nesting() - entry->nesting())); \ | |
| 175 } else { \ | |
| 176 prev_entry = entry; \ | |
| 177 } \ | |
| 178 } \ | |
| 179 } \ | |
| 180 | |
| 181 #define MUST_KILL_MEMORY(must_kill, entry, value) \ | |
| 182 bool must_kill = value->as_LoadField() != NULL || value->as_LoadIndexed() != NULL; | |
| 183 | |
| 184 #define MUST_KILL_ARRAY(must_kill, entry, value) \ | |
| 185 bool must_kill = value->as_LoadIndexed() != NULL \ | |
| 186 && value->type()->tag() == type->tag(); | |
| 187 | |
| 188 #define MUST_KILL_FIELD(must_kill, entry, value) \ | |
| 189 /* ciField's are not unique; must compare their contents */ \ | |
| 190 LoadField* lf = value->as_LoadField(); \ | |
| 191 bool must_kill = lf != NULL \ | |
| 192 && lf->field()->holder() == field->holder() \ | |
|
6618
0bfcb7a3e12d
7171824: assert(_offset >= 1) failed: illegal call to offset()
roland
parents:
4871
diff
changeset
|
193 && (all_offsets || lf->field()->offset() == field->offset()); |
| 0 | 194 |
| 195 | |
| 196 void ValueMap::kill_memory() { | |
| 197 GENERIC_KILL_VALUE(MUST_KILL_MEMORY); | |
| 198 } | |
| 199 | |
| 200 void ValueMap::kill_array(ValueType* type) { | |
| 201 GENERIC_KILL_VALUE(MUST_KILL_ARRAY); | |
| 202 } | |
| 203 | |
|
6618
0bfcb7a3e12d
7171824: assert(_offset >= 1) failed: illegal call to offset()
roland
parents:
4871
diff
changeset
|
204 void ValueMap::kill_field(ciField* field, bool all_offsets) { |
| 0 | 205 GENERIC_KILL_VALUE(MUST_KILL_FIELD); |
| 206 } | |
| 207 | |
| 208 void ValueMap::kill_map(ValueMap* map) { | |
| 209 assert(is_global_value_numbering(), "only for global value numbering"); | |
| 210 _killed_values.set_union(&map->_killed_values); | |
| 211 } | |
| 212 | |
| 213 void ValueMap::kill_all() { | |
| 214 assert(is_local_value_numbering(), "only for local value numbering"); | |
| 215 for (int i = size() - 1; i >= 0; i--) { | |
| 216 _entries.at_put(i, NULL); | |
| 217 } | |
| 218 _entry_count = 0; | |
| 219 } | |
| 220 | |
| 221 | |
| 222 #ifndef PRODUCT | |
| 223 | |
| 224 void ValueMap::print() { | |
| 225 tty->print_cr("(size %d, entries %d, nesting %d)", size(), entry_count(), nesting()); | |
| 226 | |
| 227 int entries = 0; | |
| 228 for (int i = 0; i < size(); i++) { | |
| 229 if (entry_at(i) != NULL) { | |
| 230 tty->print(" %2d: ", i); | |
| 231 for (ValueMapEntry* entry = entry_at(i); entry != NULL; entry = entry->next()) { | |
| 232 Value value = entry->value(); | |
| 233 tty->print("%s %c%d (%s%d) -> ", value->name(), value->type()->tchar(), value->id(), is_killed(value) ? "x" : "", entry->nesting()); | |
| 234 entries++; | |
| 235 } | |
| 236 tty->print_cr("NULL"); | |
| 237 } | |
| 238 } | |
| 239 | |
| 240 _killed_values.print(); | |
| 241 assert(entry_count() == entries, "entry_count incorrect"); | |
| 242 } | |
| 243 | |
| 244 void ValueMap::reset_statistics() { | |
| 245 _number_of_finds = 0; | |
| 246 _number_of_hits = 0; | |
| 247 _number_of_kills = 0; | |
| 248 } | |
| 249 | |
| 250 void ValueMap::print_statistics() { | |
| 251 float hit_rate = 0; | |
| 252 if (_number_of_finds != 0) { | |
| 253 hit_rate = (float)_number_of_hits / _number_of_finds; | |
| 254 } | |
| 255 | |
| 256 tty->print_cr("finds:%3d hits:%3d kills:%3d hit rate: %1.4f", _number_of_finds, _number_of_hits, _number_of_kills, hit_rate); | |
| 257 } | |
| 258 | |
| 259 #endif | |
| 260 | |
| 261 | |
| 262 | |
| 263 class ShortLoopOptimizer : public ValueNumberingVisitor { | |
| 264 private: | |
| 265 GlobalValueNumbering* _gvn; | |
| 266 BlockList _loop_blocks; | |
| 267 bool _too_complicated_loop; | |
| 8860 | 268 bool _has_field_store[T_ARRAY + 1]; |
| 269 bool _has_indexed_store[T_ARRAY + 1]; | |
| 0 | 270 |
| 271 // simplified access to methods of GlobalValueNumbering | |
| 272 ValueMap* current_map() { return _gvn->current_map(); } | |
| 273 ValueMap* value_map_of(BlockBegin* block) { return _gvn->value_map_of(block); } | |
| 274 | |
| 275 // implementation for abstract methods of ValueNumberingVisitor | |
|
6618
0bfcb7a3e12d
7171824: assert(_offset >= 1) failed: illegal call to offset()
roland
parents:
4871
diff
changeset
|
276 void kill_memory() { _too_complicated_loop = true; } |
| 8860 | 277 void kill_field(ciField* field, bool all_offsets) { |
| 278 current_map()->kill_field(field, all_offsets); | |
| 279 assert(field->type()->basic_type() >= 0 && field->type()->basic_type() <= T_ARRAY, "Invalid type"); | |
| 280 _has_field_store[field->type()->basic_type()] = true; | |
| 281 } | |
| 282 void kill_array(ValueType* type) { | |
| 283 current_map()->kill_array(type); | |
| 284 BasicType basic_type = as_BasicType(type); assert(basic_type >= 0 && basic_type <= T_ARRAY, "Invalid type"); | |
| 285 _has_indexed_store[basic_type] = true; | |
| 286 } | |
| 0 | 287 |
| 288 public: | |
| 289 ShortLoopOptimizer(GlobalValueNumbering* gvn) | |
| 290 : _gvn(gvn) | |
| 291 , _loop_blocks(ValueMapMaxLoopSize) | |
| 292 , _too_complicated_loop(false) | |
| 293 { | |
| 8860 | 294 for (int i=0; i<= T_ARRAY; i++){ |
| 295 _has_field_store[i] = false; | |
| 296 _has_indexed_store[i] = false; | |
| 297 } | |
| 298 } | |
| 299 | |
| 300 bool has_field_store(BasicType type) { | |
| 301 assert(type >= 0 && type <= T_ARRAY, "Invalid type"); | |
| 302 return _has_field_store[type]; | |
| 303 } | |
| 304 | |
| 305 bool has_indexed_store(BasicType type) { | |
| 306 assert(type >= 0 && type <= T_ARRAY, "Invalid type"); | |
| 307 return _has_indexed_store[type]; | |
| 0 | 308 } |
| 309 | |
| 310 bool process(BlockBegin* loop_header); | |
| 311 }; | |
| 312 | |
| 8860 | 313 class LoopInvariantCodeMotion : public StackObj { |
| 314 private: | |
| 315 GlobalValueNumbering* _gvn; | |
| 316 ShortLoopOptimizer* _short_loop_optimizer; | |
| 317 Instruction* _insertion_point; | |
| 318 ValueStack * _state; | |
|
9081
84ab5667f290
8011706: specjvm2008 test xml.transform gets array bound exception with c1
roland
parents:
8860
diff
changeset
|
319 bool _insert_is_pred; |
| 8860 | 320 |
| 321 void set_invariant(Value v) const { _gvn->set_processed(v); } | |
| 322 bool is_invariant(Value v) const { return _gvn->is_processed(v); } | |
| 323 | |
| 324 void process_block(BlockBegin* block); | |
| 325 | |
| 326 public: | |
| 327 LoopInvariantCodeMotion(ShortLoopOptimizer *slo, GlobalValueNumbering* gvn, BlockBegin* loop_header, BlockList* loop_blocks); | |
| 328 }; | |
| 329 | |
| 330 LoopInvariantCodeMotion::LoopInvariantCodeMotion(ShortLoopOptimizer *slo, GlobalValueNumbering* gvn, BlockBegin* loop_header, BlockList* loop_blocks) | |
| 331 : _gvn(gvn), _short_loop_optimizer(slo) { | |
| 332 | |
| 333 TRACE_VALUE_NUMBERING(tty->print_cr("using loop invariant code motion loop_header = %d", loop_header->block_id())); | |
| 334 TRACE_VALUE_NUMBERING(tty->print_cr("** loop invariant code motion for short loop B%d", loop_header->block_id())); | |
| 335 | |
| 336 BlockBegin* insertion_block = loop_header->dominator(); | |
| 337 if (insertion_block->number_of_preds() == 0) { | |
| 338 return; // only the entry block does not have a predecessor | |
| 339 } | |
| 340 | |
| 341 assert(insertion_block->end()->as_Base() == NULL, "cannot insert into entry block"); | |
| 342 _insertion_point = insertion_block->end()->prev(); | |
|
9081
84ab5667f290
8011706: specjvm2008 test xml.transform gets array bound exception with c1
roland
parents:
8860
diff
changeset
|
343 _insert_is_pred = loop_header->is_predecessor(insertion_block); |
| 8860 | 344 |
| 345 BlockEnd *block_end = insertion_block->end(); | |
| 346 _state = block_end->state_before(); | |
| 347 | |
| 348 if (!_state) { | |
| 349 // If, TableSwitch and LookupSwitch always have state_before when | |
| 350 // loop invariant code motion happens.. | |
| 351 assert(block_end->as_Goto(), "Block has to be goto"); | |
| 352 _state = block_end->state(); | |
| 353 } | |
| 354 | |
| 355 // the loop_blocks are filled by going backward from the loop header, so this processing order is best | |
| 356 assert(loop_blocks->at(0) == loop_header, "loop header must be first loop block"); | |
| 357 process_block(loop_header); | |
| 358 for (int i = loop_blocks->length() - 1; i >= 1; i--) { | |
| 359 process_block(loop_blocks->at(i)); | |
| 360 } | |
| 361 } | |
| 362 | |
| 363 void LoopInvariantCodeMotion::process_block(BlockBegin* block) { | |
| 364 TRACE_VALUE_NUMBERING(tty->print_cr("processing block B%d", block->block_id())); | |
| 365 | |
| 366 Instruction* prev = block; | |
| 367 Instruction* cur = block->next(); | |
| 368 | |
| 369 while (cur != NULL) { | |
| 370 | |
| 371 // determine if cur instruction is loop invariant | |
| 372 // only selected instruction types are processed here | |
| 373 bool cur_invariant = false; | |
| 374 | |
| 375 if (cur->as_Constant() != NULL) { | |
| 376 cur_invariant = !cur->can_trap(); | |
| 377 } else if (cur->as_ArithmeticOp() != NULL || cur->as_LogicOp() != NULL || cur->as_ShiftOp() != NULL) { | |
| 378 assert(cur->as_Op2() != NULL, "must be Op2"); | |
| 379 Op2* op2 = (Op2*)cur; | |
| 380 cur_invariant = !op2->can_trap() && is_invariant(op2->x()) && is_invariant(op2->y()); | |
| 381 } else if (cur->as_LoadField() != NULL) { | |
| 382 LoadField* lf = (LoadField*)cur; | |
| 383 // deoptimizes on NullPointerException | |
|
9081
84ab5667f290
8011706: specjvm2008 test xml.transform gets array bound exception with c1
roland
parents:
8860
diff
changeset
|
384 cur_invariant = !lf->needs_patching() && !lf->field()->is_volatile() && !_short_loop_optimizer->has_field_store(lf->field()->type()->basic_type()) && is_invariant(lf->obj()) && _insert_is_pred; |
| 8860 | 385 } else if (cur->as_ArrayLength() != NULL) { |
| 386 ArrayLength *length = cur->as_ArrayLength(); | |
| 387 cur_invariant = is_invariant(length->array()); | |
| 388 } else if (cur->as_LoadIndexed() != NULL) { | |
| 389 LoadIndexed *li = (LoadIndexed *)cur->as_LoadIndexed(); | |
|
9081
84ab5667f290
8011706: specjvm2008 test xml.transform gets array bound exception with c1
roland
parents:
8860
diff
changeset
|
390 cur_invariant = !_short_loop_optimizer->has_indexed_store(as_BasicType(cur->type())) && is_invariant(li->array()) && is_invariant(li->index()) && _insert_is_pred; |
| 8860 | 391 } |
| 392 | |
| 393 if (cur_invariant) { | |
| 394 // perform value numbering and mark instruction as loop-invariant | |
| 395 _gvn->substitute(cur); | |
| 396 | |
| 397 if (cur->as_Constant() == NULL) { | |
| 398 // ensure that code for non-constant instructions is always generated | |
| 399 cur->pin(); | |
| 400 } | |
| 401 | |
| 402 // remove cur instruction from loop block and append it to block before loop | |
| 403 Instruction* next = cur->next(); | |
| 404 Instruction* in = _insertion_point->next(); | |
| 405 _insertion_point = _insertion_point->set_next(cur); | |
| 406 cur->set_next(in); | |
| 407 | |
| 408 // Deoptimize on exception | |
| 409 cur->set_flag(Instruction::DeoptimizeOnException, true); | |
| 410 | |
| 411 // Clear exception handlers | |
| 412 cur->set_exception_handlers(NULL); | |
| 413 | |
| 414 TRACE_VALUE_NUMBERING(tty->print_cr("Instruction %c%d is loop invariant", cur->type()->tchar(), cur->id())); | |
| 415 | |
| 416 if (cur->state_before() != NULL) { | |
| 417 cur->set_state_before(_state->copy()); | |
| 418 } | |
| 419 if (cur->exception_state() != NULL) { | |
| 420 cur->set_exception_state(_state->copy()); | |
| 421 } | |
| 422 | |
| 423 cur = prev->set_next(next); | |
| 424 | |
| 425 } else { | |
| 426 prev = cur; | |
| 427 cur = cur->next(); | |
| 428 } | |
| 429 } | |
| 430 } | |
| 0 | 431 |
| 432 bool ShortLoopOptimizer::process(BlockBegin* loop_header) { | |
| 433 TRACE_VALUE_NUMBERING(tty->print_cr("** loop header block")); | |
| 434 | |
| 435 _too_complicated_loop = false; | |
| 436 _loop_blocks.clear(); | |
| 437 _loop_blocks.append(loop_header); | |
| 438 | |
| 439 for (int i = 0; i < _loop_blocks.length(); i++) { | |
| 440 BlockBegin* block = _loop_blocks.at(i); | |
| 441 TRACE_VALUE_NUMBERING(tty->print_cr("processing loop block B%d", block->block_id())); | |
| 442 | |
| 443 if (block->is_set(BlockBegin::exception_entry_flag)) { | |
| 444 // this would be too complicated | |
| 445 return false; | |
| 446 } | |
| 447 | |
| 448 // add predecessors to worklist | |
| 449 for (int j = block->number_of_preds() - 1; j >= 0; j--) { | |
| 450 BlockBegin* pred = block->pred_at(j); | |
| 451 | |
| 8860 | 452 if (pred->is_set(BlockBegin::osr_entry_flag)) { |
| 453 return false; | |
| 454 } | |
| 455 | |
| 0 | 456 ValueMap* pred_map = value_map_of(pred); |
| 457 if (pred_map != NULL) { | |
| 458 current_map()->kill_map(pred_map); | |
| 459 } else if (!_loop_blocks.contains(pred)) { | |
| 460 if (_loop_blocks.length() >= ValueMapMaxLoopSize) { | |
| 461 return false; | |
| 462 } | |
| 463 _loop_blocks.append(pred); | |
| 464 } | |
| 465 } | |
| 466 | |
| 467 // use the instruction visitor for killing values | |
| 468 for (Value instr = block->next(); instr != NULL; instr = instr->next()) { | |
| 469 instr->visit(this); | |
| 470 if (_too_complicated_loop) { | |
| 471 return false; | |
| 472 } | |
| 473 } | |
| 474 } | |
| 475 | |
| 8860 | 476 bool optimistic = this->_gvn->compilation()->is_optimistic(); |
| 477 | |
| 478 if (UseLoopInvariantCodeMotion && optimistic) { | |
| 479 LoopInvariantCodeMotion code_motion(this, _gvn, loop_header, &_loop_blocks); | |
| 480 } | |
| 481 | |
| 0 | 482 TRACE_VALUE_NUMBERING(tty->print_cr("** loop successfully optimized")); |
| 483 return true; | |
| 484 } | |
| 485 | |
| 486 | |
| 487 GlobalValueNumbering::GlobalValueNumbering(IR* ir) | |
| 488 : _current_map(NULL) | |
| 489 , _value_maps(ir->linear_scan_order()->length(), NULL) | |
| 8860 | 490 , _compilation(ir->compilation()) |
| 0 | 491 { |
| 492 TRACE_VALUE_NUMBERING(tty->print_cr("****** start of global value numbering")); | |
| 493 | |
| 494 ShortLoopOptimizer short_loop_optimizer(this); | |
| 495 | |
| 496 BlockList* blocks = ir->linear_scan_order(); | |
| 497 int num_blocks = blocks->length(); | |
| 498 | |
| 499 BlockBegin* start_block = blocks->at(0); | |
| 500 assert(start_block == ir->start() && start_block->number_of_preds() == 0 && start_block->dominator() == NULL, "must be start block"); | |
| 501 assert(start_block->next()->as_Base() != NULL && start_block->next()->next() == NULL, "start block must not have instructions"); | |
| 502 | |
| 8860 | 503 // method parameters are not linked in instructions list, so process them separateley |
| 504 for_each_state_value(start_block->state(), value, | |
| 505 assert(value->as_Local() != NULL, "only method parameters allowed"); | |
| 506 set_processed(value); | |
| 507 ); | |
| 508 | |
| 0 | 509 // initial, empty value map with nesting 0 |
| 510 set_value_map_of(start_block, new ValueMap()); | |
| 511 | |
| 512 for (int i = 1; i < num_blocks; i++) { | |
| 513 BlockBegin* block = blocks->at(i); | |
| 514 TRACE_VALUE_NUMBERING(tty->print_cr("**** processing block B%d", block->block_id())); | |
| 515 | |
| 516 int num_preds = block->number_of_preds(); | |
| 517 assert(num_preds > 0, "block must have predecessors"); | |
| 518 | |
| 519 BlockBegin* dominator = block->dominator(); | |
| 520 assert(dominator != NULL, "dominator must exist"); | |
| 521 assert(value_map_of(dominator) != NULL, "value map of dominator must exist"); | |
| 522 | |
| 523 // create new value map with increased nesting | |
| 524 _current_map = new ValueMap(value_map_of(dominator)); | |
| 525 | |
| 8860 | 526 if (num_preds == 1 && !block->is_set(BlockBegin::exception_entry_flag)) { |
| 0 | 527 assert(dominator == block->pred_at(0), "dominator must be equal to predecessor"); |
| 528 // nothing to do here | |
| 529 | |
| 530 } else if (block->is_set(BlockBegin::linear_scan_loop_header_flag)) { | |
| 531 // block has incoming backward branches -> try to optimize short loops | |
| 532 if (!short_loop_optimizer.process(block)) { | |
| 533 // loop is too complicated, so kill all memory loads because there might be | |
| 534 // stores to them in the loop | |
| 535 current_map()->kill_memory(); | |
| 536 } | |
| 537 | |
| 538 } else { | |
| 539 // only incoming forward branches that are already processed | |
| 540 for (int j = 0; j < num_preds; j++) { | |
| 541 BlockBegin* pred = block->pred_at(j); | |
| 542 ValueMap* pred_map = value_map_of(pred); | |
| 543 | |
| 544 if (pred_map != NULL) { | |
| 545 // propagate killed values of the predecessor to this block | |
| 546 current_map()->kill_map(value_map_of(pred)); | |
| 547 } else { | |
| 548 // kill all memory loads because predecessor not yet processed | |
| 549 // (this can happen with non-natural loops and OSR-compiles) | |
| 550 current_map()->kill_memory(); | |
| 551 } | |
| 552 } | |
| 553 } | |
| 554 | |
| 8860 | 555 // phi functions are not linked in instructions list, so process them separateley |
| 556 for_each_phi_fun(block, phi, | |
| 557 set_processed(phi); | |
| 558 ); | |
| 0 | 559 |
| 560 TRACE_VALUE_NUMBERING(tty->print("value map before processing block: "); current_map()->print()); | |
| 561 | |
| 562 // visit all instructions of this block | |
| 563 for (Value instr = block->next(); instr != NULL; instr = instr->next()) { | |
| 564 // check if instruction kills any values | |
| 565 instr->visit(this); | |
| 8860 | 566 // perform actual value numbering |
| 567 substitute(instr); | |
| 0 | 568 } |
| 569 | |
| 570 // remember value map for successors | |
| 571 set_value_map_of(block, current_map()); | |
| 572 } | |
| 573 | |
| 8860 | 574 if (_has_substitutions) { |
| 0 | 575 SubstitutionResolver resolver(ir); |
| 576 } | |
| 577 | |
| 578 TRACE_VALUE_NUMBERING(tty->print("****** end of global value numbering. "); ValueMap::print_statistics()); | |
| 579 } | |
| 8860 | 580 |
| 581 void GlobalValueNumbering::substitute(Instruction* instr) { | |
| 582 assert(!instr->has_subst(), "substitution already set"); | |
| 583 Value subst = current_map()->find_insert(instr); | |
| 584 if (subst != instr) { | |
| 585 assert(!subst->has_subst(), "can't have a substitution"); | |
| 586 | |
| 587 TRACE_VALUE_NUMBERING(tty->print_cr("substitution for %d set to %d", instr->id(), subst->id())); | |
| 588 instr->set_subst(subst); | |
| 589 _has_substitutions = true; | |
| 590 } | |
| 591 set_processed(instr); | |
| 592 } |