Mon, 25 May 2020 14:24:27 +0800
8244407: JVM crashes after transformation in C2 IdealLoopTree::split_fall_in
Reviewed-by: thartmann, kvn, andrew
Contributed-by: zhouyong44@huawei.com
duke@435 | 1 | /* |
mikael@6198 | 2 | * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "memory/allocation.inline.hpp" |
stefank@2314 | 27 | #include "opto/callnode.hpp" |
stefank@2314 | 28 | #include "opto/chaitin.hpp" |
stefank@2314 | 29 | #include "opto/live.hpp" |
stefank@2314 | 30 | #include "opto/machnode.hpp" |
duke@435 | 31 | |
duke@435 | 32 | |
duke@435 | 33 | // Compute live-in/live-out. We use a totally incremental algorithm. The LIVE |
duke@435 | 34 | // problem is monotonic. The steady-state solution looks like this: pull a |
duke@435 | 35 | // block from the worklist. It has a set of delta's - values which are newly |
duke@435 | 36 | // live-in from the block. Push these to the live-out sets of all predecessor |
duke@435 | 37 | // blocks. At each predecessor, the new live-out values are ANDed with what is |
duke@435 | 38 | // already live-out (extra stuff is added to the live-out sets). Then the |
duke@435 | 39 | // remaining new live-out values are ANDed with what is locally defined. |
duke@435 | 40 | // Leftover bits become the new live-in for the predecessor block, and the pred |
duke@435 | 41 | // block is put on the worklist. |
duke@435 | 42 | // The locally live-in stuff is computed once and added to predecessor |
twisti@1040 | 43 | // live-out sets. This separate compilation is done in the outer loop below. |
neliasso@4949 | 44 | PhaseLive::PhaseLive( const PhaseCFG &cfg, const LRG_List &names, Arena *arena ) : Phase(LIVE), _cfg(cfg), _names(names), _arena(arena), _live(0) { |
duke@435 | 45 | } |
duke@435 | 46 | |
duke@435 | 47 | void PhaseLive::compute(uint maxlrg) { |
duke@435 | 48 | _maxlrg = maxlrg; |
duke@435 | 49 | _worklist = new (_arena) Block_List(); |
duke@435 | 50 | |
duke@435 | 51 | // Init the sparse live arrays. This data is live on exit from here! |
duke@435 | 52 | // The _live info is the live-out info. |
adlertz@5539 | 53 | _live = (IndexSet*)_arena->Amalloc(sizeof(IndexSet) * _cfg.number_of_blocks()); |
duke@435 | 54 | uint i; |
adlertz@5539 | 55 | for (i = 0; i < _cfg.number_of_blocks(); i++) { |
duke@435 | 56 | _live[i].initialize(_maxlrg); |
duke@435 | 57 | } |
duke@435 | 58 | |
duke@435 | 59 | // Init the sparse arrays for delta-sets. |
duke@435 | 60 | ResourceMark rm; // Nuke temp storage on exit |
duke@435 | 61 | |
duke@435 | 62 | // Does the memory used by _defs and _deltas get reclaimed? Does it matter? TT |
duke@435 | 63 | |
duke@435 | 64 | // Array of values defined locally in blocks |
adlertz@5539 | 65 | _defs = NEW_RESOURCE_ARRAY(IndexSet,_cfg.number_of_blocks()); |
adlertz@5539 | 66 | for (i = 0; i < _cfg.number_of_blocks(); i++) { |
duke@435 | 67 | _defs[i].initialize(_maxlrg); |
duke@435 | 68 | } |
duke@435 | 69 | |
duke@435 | 70 | // Array of delta-set pointers, indexed by block pre_order-1. |
adlertz@5539 | 71 | _deltas = NEW_RESOURCE_ARRAY(IndexSet*,_cfg.number_of_blocks()); |
adlertz@5539 | 72 | memset( _deltas, 0, sizeof(IndexSet*)* _cfg.number_of_blocks()); |
duke@435 | 73 | |
duke@435 | 74 | _free_IndexSet = NULL; |
duke@435 | 75 | |
duke@435 | 76 | // Blocks having done pass-1 |
duke@435 | 77 | VectorSet first_pass(Thread::current()->resource_area()); |
duke@435 | 78 | |
duke@435 | 79 | // Outer loop: must compute local live-in sets and push into predecessors. |
adlertz@5539 | 80 | for (uint j = _cfg.number_of_blocks(); j > 0; j--) { |
adlertz@5539 | 81 | Block* block = _cfg.get_block(j - 1); |
duke@435 | 82 | |
duke@435 | 83 | // Compute the local live-in set. Start with any new live-out bits. |
adlertz@5539 | 84 | IndexSet* use = getset(block); |
adlertz@5539 | 85 | IndexSet* def = &_defs[block->_pre_order-1]; |
duke@435 | 86 | DEBUG_ONLY(IndexSet *def_outside = getfreeset();) |
duke@435 | 87 | uint i; |
adlertz@5635 | 88 | for (i = block->number_of_nodes(); i > 1; i--) { |
adlertz@5635 | 89 | Node* n = block->get_node(i-1); |
adlertz@5539 | 90 | if (n->is_Phi()) { |
adlertz@5539 | 91 | break; |
adlertz@5539 | 92 | } |
duke@435 | 93 | |
adlertz@5722 | 94 | uint r = _names.at(n->_idx); |
duke@435 | 95 | assert(!def_outside->member(r), "Use of external LRG overlaps the same LRG defined in this block"); |
duke@435 | 96 | def->insert( r ); |
duke@435 | 97 | use->remove( r ); |
duke@435 | 98 | uint cnt = n->req(); |
adlertz@5539 | 99 | for (uint k = 1; k < cnt; k++) { |
duke@435 | 100 | Node *nk = n->in(k); |
duke@435 | 101 | uint nkidx = nk->_idx; |
adlertz@5539 | 102 | if (_cfg.get_block_for_node(nk) != block) { |
adlertz@5722 | 103 | uint u = _names.at(nkidx); |
adlertz@5539 | 104 | use->insert(u); |
adlertz@5539 | 105 | DEBUG_ONLY(def_outside->insert(u);) |
duke@435 | 106 | } |
duke@435 | 107 | } |
duke@435 | 108 | } |
duke@435 | 109 | #ifdef ASSERT |
duke@435 | 110 | def_outside->set_next(_free_IndexSet); |
duke@435 | 111 | _free_IndexSet = def_outside; // Drop onto free list |
duke@435 | 112 | #endif |
duke@435 | 113 | // Remove anything defined by Phis and the block start instruction |
adlertz@5539 | 114 | for (uint k = i; k > 0; k--) { |
adlertz@5722 | 115 | uint r = _names.at(block->get_node(k - 1)->_idx); |
adlertz@5539 | 116 | def->insert(r); |
adlertz@5539 | 117 | use->remove(r); |
duke@435 | 118 | } |
duke@435 | 119 | |
duke@435 | 120 | // Push these live-in things to predecessors |
adlertz@5539 | 121 | for (uint l = 1; l < block->num_preds(); l++) { |
adlertz@5539 | 122 | Block* p = _cfg.get_block_for_node(block->pred(l)); |
adlertz@5539 | 123 | add_liveout(p, use, first_pass); |
duke@435 | 124 | |
duke@435 | 125 | // PhiNode uses go in the live-out set of prior blocks. |
adlertz@5539 | 126 | for (uint k = i; k > 0; k--) { |
adlertz@5722 | 127 | add_liveout(p, _names.at(block->get_node(k-1)->in(l)->_idx), first_pass); |
adlertz@5539 | 128 | } |
duke@435 | 129 | } |
adlertz@5539 | 130 | freeset(block); |
adlertz@5539 | 131 | first_pass.set(block->_pre_order); |
duke@435 | 132 | |
duke@435 | 133 | // Inner loop: blocks that picked up new live-out values to be propagated |
adlertz@5539 | 134 | while (_worklist->size()) { |
adlertz@5539 | 135 | Block* block = _worklist->pop(); |
adlertz@5539 | 136 | IndexSet *delta = getset(block); |
duke@435 | 137 | assert( delta->count(), "missing delta set" ); |
duke@435 | 138 | |
duke@435 | 139 | // Add new-live-in to predecessors live-out sets |
adlertz@5539 | 140 | for (uint l = 1; l < block->num_preds(); l++) { |
adlertz@5539 | 141 | Block* predecessor = _cfg.get_block_for_node(block->pred(l)); |
adlertz@5539 | 142 | add_liveout(predecessor, delta, first_pass); |
adlertz@5509 | 143 | } |
duke@435 | 144 | |
adlertz@5539 | 145 | freeset(block); |
duke@435 | 146 | } // End of while-worklist-not-empty |
duke@435 | 147 | |
duke@435 | 148 | } // End of for-all-blocks-outer-loop |
duke@435 | 149 | |
duke@435 | 150 | // We explicitly clear all of the IndexSets which we are about to release. |
duke@435 | 151 | // This allows us to recycle their internal memory into IndexSet's free list. |
duke@435 | 152 | |
adlertz@5539 | 153 | for (i = 0; i < _cfg.number_of_blocks(); i++) { |
duke@435 | 154 | _defs[i].clear(); |
duke@435 | 155 | if (_deltas[i]) { |
duke@435 | 156 | // Is this always true? |
duke@435 | 157 | _deltas[i]->clear(); |
duke@435 | 158 | } |
duke@435 | 159 | } |
duke@435 | 160 | IndexSet *free = _free_IndexSet; |
duke@435 | 161 | while (free != NULL) { |
duke@435 | 162 | IndexSet *temp = free; |
duke@435 | 163 | free = free->next(); |
duke@435 | 164 | temp->clear(); |
duke@435 | 165 | } |
duke@435 | 166 | |
duke@435 | 167 | } |
duke@435 | 168 | |
duke@435 | 169 | #ifndef PRODUCT |
duke@435 | 170 | void PhaseLive::stats(uint iters) const { |
duke@435 | 171 | } |
duke@435 | 172 | #endif |
duke@435 | 173 | |
duke@435 | 174 | // Get an IndexSet for a block. Return existing one, if any. Make a new |
duke@435 | 175 | // empty one if a prior one does not exist. |
duke@435 | 176 | IndexSet *PhaseLive::getset( Block *p ) { |
duke@435 | 177 | IndexSet *delta = _deltas[p->_pre_order-1]; |
duke@435 | 178 | if( !delta ) // Not on worklist? |
duke@435 | 179 | // Get a free set; flag as being on worklist |
duke@435 | 180 | delta = _deltas[p->_pre_order-1] = getfreeset(); |
duke@435 | 181 | return delta; // Return set of new live-out items |
duke@435 | 182 | } |
duke@435 | 183 | |
duke@435 | 184 | // Pull from free list, or allocate. Internal allocation on the returned set |
duke@435 | 185 | // is always from thread local storage. |
duke@435 | 186 | IndexSet *PhaseLive::getfreeset( ) { |
duke@435 | 187 | IndexSet *f = _free_IndexSet; |
duke@435 | 188 | if( !f ) { |
duke@435 | 189 | f = new IndexSet; |
duke@435 | 190 | // f->set_arena(Thread::current()->resource_area()); |
duke@435 | 191 | f->initialize(_maxlrg, Thread::current()->resource_area()); |
duke@435 | 192 | } else { |
duke@435 | 193 | // Pull from free list |
duke@435 | 194 | _free_IndexSet = f->next(); |
duke@435 | 195 | //f->_cnt = 0; // Reset to empty |
duke@435 | 196 | // f->set_arena(Thread::current()->resource_area()); |
duke@435 | 197 | f->initialize(_maxlrg, Thread::current()->resource_area()); |
duke@435 | 198 | } |
duke@435 | 199 | return f; |
duke@435 | 200 | } |
duke@435 | 201 | |
duke@435 | 202 | // Free an IndexSet from a block. |
duke@435 | 203 | void PhaseLive::freeset( const Block *p ) { |
duke@435 | 204 | IndexSet *f = _deltas[p->_pre_order-1]; |
duke@435 | 205 | f->set_next(_free_IndexSet); |
duke@435 | 206 | _free_IndexSet = f; // Drop onto free list |
duke@435 | 207 | _deltas[p->_pre_order-1] = NULL; |
duke@435 | 208 | } |
duke@435 | 209 | |
duke@435 | 210 | // Add a live-out value to a given blocks live-out set. If it is new, then |
duke@435 | 211 | // also add it to the delta set and stick the block on the worklist. |
duke@435 | 212 | void PhaseLive::add_liveout( Block *p, uint r, VectorSet &first_pass ) { |
duke@435 | 213 | IndexSet *live = &_live[p->_pre_order-1]; |
duke@435 | 214 | if( live->insert(r) ) { // If actually inserted... |
duke@435 | 215 | // We extended the live-out set. See if the value is generated locally. |
duke@435 | 216 | // If it is not, then we must extend the live-in set. |
duke@435 | 217 | if( !_defs[p->_pre_order-1].member( r ) ) { |
duke@435 | 218 | if( !_deltas[p->_pre_order-1] && // Not on worklist? |
duke@435 | 219 | first_pass.test(p->_pre_order) ) |
duke@435 | 220 | _worklist->push(p); // Actually go on worklist if already 1st pass |
duke@435 | 221 | getset(p)->insert(r); |
duke@435 | 222 | } |
duke@435 | 223 | } |
duke@435 | 224 | } |
duke@435 | 225 | |
duke@435 | 226 | // Add a vector of live-out values to a given blocks live-out set. |
duke@435 | 227 | void PhaseLive::add_liveout( Block *p, IndexSet *lo, VectorSet &first_pass ) { |
duke@435 | 228 | IndexSet *live = &_live[p->_pre_order-1]; |
duke@435 | 229 | IndexSet *defs = &_defs[p->_pre_order-1]; |
duke@435 | 230 | IndexSet *on_worklist = _deltas[p->_pre_order-1]; |
duke@435 | 231 | IndexSet *delta = on_worklist ? on_worklist : getfreeset(); |
duke@435 | 232 | |
duke@435 | 233 | IndexSetIterator elements(lo); |
duke@435 | 234 | uint r; |
duke@435 | 235 | while ((r = elements.next()) != 0) { |
duke@435 | 236 | if( live->insert(r) && // If actually inserted... |
duke@435 | 237 | !defs->member( r ) ) // and not defined locally |
duke@435 | 238 | delta->insert(r); // Then add to live-in set |
duke@435 | 239 | } |
duke@435 | 240 | |
duke@435 | 241 | if( delta->count() ) { // If actually added things |
duke@435 | 242 | _deltas[p->_pre_order-1] = delta; // Flag as on worklist now |
duke@435 | 243 | if( !on_worklist && // Not on worklist? |
duke@435 | 244 | first_pass.test(p->_pre_order) ) |
duke@435 | 245 | _worklist->push(p); // Actually go on worklist if already 1st pass |
duke@435 | 246 | } else { // Nothing there; just free it |
duke@435 | 247 | delta->set_next(_free_IndexSet); |
duke@435 | 248 | _free_IndexSet = delta; // Drop onto free list |
duke@435 | 249 | } |
duke@435 | 250 | } |
duke@435 | 251 | |
duke@435 | 252 | #ifndef PRODUCT |
duke@435 | 253 | // Dump the live-out set for a block |
duke@435 | 254 | void PhaseLive::dump( const Block *b ) const { |
duke@435 | 255 | tty->print("Block %d: ",b->_pre_order); |
duke@435 | 256 | tty->print("LiveOut: "); _live[b->_pre_order-1].dump(); |
adlertz@5635 | 257 | uint cnt = b->number_of_nodes(); |
duke@435 | 258 | for( uint i=0; i<cnt; i++ ) { |
adlertz@5722 | 259 | tty->print("L%d/", _names.at(b->get_node(i)->_idx)); |
adlertz@5635 | 260 | b->get_node(i)->dump(); |
duke@435 | 261 | } |
duke@435 | 262 | tty->print("\n"); |
duke@435 | 263 | } |
duke@435 | 264 | |
duke@435 | 265 | // Verify that base pointers and derived pointers are still sane. |
duke@435 | 266 | void PhaseChaitin::verify_base_ptrs( ResourceArea *a ) const { |
kvn@985 | 267 | #ifdef ASSERT |
kvn@985 | 268 | Unique_Node_List worklist(a); |
adlertz@5539 | 269 | for (uint i = 0; i < _cfg.number_of_blocks(); i++) { |
adlertz@5539 | 270 | Block* block = _cfg.get_block(i); |
adlertz@5539 | 271 | for (uint j = block->end_idx() + 1; j > 1; j--) { |
adlertz@5635 | 272 | Node* n = block->get_node(j-1); |
adlertz@5539 | 273 | if (n->is_Phi()) { |
adlertz@5539 | 274 | break; |
adlertz@5539 | 275 | } |
duke@435 | 276 | // Found a safepoint? |
adlertz@5539 | 277 | if (n->is_MachSafePoint()) { |
duke@435 | 278 | MachSafePointNode *sfpt = n->as_MachSafePoint(); |
duke@435 | 279 | JVMState* jvms = sfpt->jvms(); |
duke@435 | 280 | if (jvms != NULL) { |
duke@435 | 281 | // Now scan for a live derived pointer |
duke@435 | 282 | if (jvms->oopoff() < sfpt->req()) { |
duke@435 | 283 | // Check each derived/base pair |
kvn@985 | 284 | for (uint idx = jvms->oopoff(); idx < sfpt->req(); idx++) { |
duke@435 | 285 | Node *check = sfpt->in(idx); |
kvn@985 | 286 | bool is_derived = ((idx - jvms->oopoff()) & 1) == 0; |
duke@435 | 287 | // search upwards through spills and spill phis for AddP |
kvn@985 | 288 | worklist.clear(); |
kvn@985 | 289 | worklist.push(check); |
kvn@985 | 290 | uint k = 0; |
kvn@985 | 291 | while( k < worklist.size() ) { |
kvn@985 | 292 | check = worklist.at(k); |
kvn@985 | 293 | assert(check,"Bad base or derived pointer"); |
kvn@985 | 294 | // See PhaseChaitin::find_base_for_derived() for all cases. |
kvn@985 | 295 | int isc = check->is_Copy(); |
kvn@985 | 296 | if( isc ) { |
kvn@985 | 297 | worklist.push(check->in(isc)); |
kvn@985 | 298 | } else if( check->is_Phi() ) { |
kvn@985 | 299 | for (uint m = 1; m < check->req(); m++) |
kvn@985 | 300 | worklist.push(check->in(m)); |
kvn@985 | 301 | } else if( check->is_Con() ) { |
kvn@985 | 302 | if (is_derived) { |
kvn@985 | 303 | // Derived is NULL+offset |
kvn@985 | 304 | assert(!is_derived || check->bottom_type()->is_ptr()->ptr() == TypePtr::Null,"Bad derived pointer"); |
kvn@985 | 305 | } else { |
kvn@985 | 306 | assert(check->bottom_type()->is_ptr()->_offset == 0,"Bad base pointer"); |
kvn@985 | 307 | // Base either ConP(NULL) or loadConP |
kvn@985 | 308 | if (check->is_Mach()) { |
kvn@985 | 309 | assert(check->as_Mach()->ideal_Opcode() == Op_ConP,"Bad base pointer"); |
kvn@985 | 310 | } else { |
kvn@985 | 311 | assert(check->Opcode() == Op_ConP && |
kvn@985 | 312 | check->bottom_type()->is_ptr()->ptr() == TypePtr::Null,"Bad base pointer"); |
kvn@985 | 313 | } |
kvn@985 | 314 | } |
kvn@985 | 315 | } else if( check->bottom_type()->is_ptr()->_offset == 0 ) { |
kvn@985 | 316 | if(check->is_Proj() || check->is_Mach() && |
kvn@985 | 317 | (check->as_Mach()->ideal_Opcode() == Op_CreateEx || |
kvn@985 | 318 | check->as_Mach()->ideal_Opcode() == Op_ThreadLocal || |
kvn@985 | 319 | check->as_Mach()->ideal_Opcode() == Op_CMoveP || |
kvn@985 | 320 | check->as_Mach()->ideal_Opcode() == Op_CheckCastPP || |
kvn@985 | 321 | #ifdef _LP64 |
kvn@985 | 322 | UseCompressedOops && check->as_Mach()->ideal_Opcode() == Op_CastPP || |
kvn@985 | 323 | UseCompressedOops && check->as_Mach()->ideal_Opcode() == Op_DecodeN || |
ehelin@5694 | 324 | UseCompressedClassPointers && check->as_Mach()->ideal_Opcode() == Op_DecodeNKlass || |
kvn@985 | 325 | #endif |
kvn@985 | 326 | check->as_Mach()->ideal_Opcode() == Op_LoadP || |
kvn@1001 | 327 | check->as_Mach()->ideal_Opcode() == Op_LoadKlass)) { |
kvn@1001 | 328 | // Valid nodes |
kvn@1001 | 329 | } else { |
kvn@1001 | 330 | check->dump(); |
kvn@985 | 331 | assert(false,"Bad base or derived pointer"); |
kvn@1001 | 332 | } |
kvn@985 | 333 | } else { |
kvn@985 | 334 | assert(is_derived,"Bad base pointer"); |
kvn@985 | 335 | assert(check->is_Mach() && check->as_Mach()->ideal_Opcode() == Op_AddP,"Bad derived pointer"); |
kvn@985 | 336 | } |
kvn@985 | 337 | k++; |
kvn@985 | 338 | assert(k < 100000,"Derived pointer checking in infinite loop"); |
duke@435 | 339 | } // End while |
duke@435 | 340 | } |
duke@435 | 341 | } // End of check for derived pointers |
duke@435 | 342 | } // End of Kcheck for debug info |
duke@435 | 343 | } // End of if found a safepoint |
duke@435 | 344 | } // End of forall instructions in block |
duke@435 | 345 | } // End of forall blocks |
kvn@985 | 346 | #endif |
duke@435 | 347 | } |
kvn@1001 | 348 | |
kvn@1001 | 349 | // Verify that graphs and base pointers are still sane. |
kvn@1001 | 350 | void PhaseChaitin::verify( ResourceArea *a, bool verify_ifg ) const { |
kvn@1001 | 351 | #ifdef ASSERT |
kvn@1001 | 352 | if( VerifyOpto || VerifyRegisterAllocator ) { |
kvn@1001 | 353 | _cfg.verify(); |
kvn@1001 | 354 | verify_base_ptrs(a); |
kvn@1001 | 355 | if(verify_ifg) |
kvn@1001 | 356 | _ifg->verify(this); |
kvn@1001 | 357 | } |
duke@435 | 358 | #endif |
kvn@1001 | 359 | } |
kvn@1001 | 360 | |
kvn@1001 | 361 | #endif |