src/share/vm/opto/live.cpp

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 117       use->remove(r);
 118     }
 119 
 120     // Push these live-in things to predecessors
 121     for (uint l = 1; l < block->num_preds(); l++) {
 122       Block* p = _cfg.get_block_for_node(block->pred(l));
 123       add_liveout(p, use, first_pass);
 124 
 125       // PhiNode uses go in the live-out set of prior blocks.
 126       for (uint k = i; k > 0; k--) {
 127         add_liveout(p, _names.at(block->get_node(k-1)->in(l)->_idx), first_pass);
 128       }
 129     }
 130     freeset(block);
 131     first_pass.set(block->_pre_order);
 132 
 133     // Inner loop: blocks that picked up new live-out values to be propagated
 134     while (_worklist->size()) {
 135       Block* block = _worklist->pop();
 136       IndexSet *delta = getset(block);
 137       assert( delta->count(), "missing delta set" );
 138 
 139       // Add new-live-in to predecessors live-out sets
 140       for (uint l = 1; l < block->num_preds(); l++) {
 141         Block* predecessor = _cfg.get_block_for_node(block->pred(l));
 142         add_liveout(predecessor, delta, first_pass);
 143       }
 144 
 145       freeset(block);
 146     } // End of while-worklist-not-empty
 147 
 148   } // End of for-all-blocks-outer-loop
 149 
 150   // We explicitly clear all of the IndexSets which we are about to release.
 151   // This allows us to recycle their internal memory into IndexSet's free list.
 152 
 153   for (i = 0; i < _cfg.number_of_blocks(); i++) {
 154     _defs[i].clear();
 155     if (_deltas[i]) {
 156       // Is this always true?
 157       _deltas[i]->clear();


 170 void PhaseLive::stats(uint iters) const {
 171 }
 172 #endif
 173 
 174 // Get an IndexSet for a block.  Return existing one, if any.  Make a new
 175 // empty one if a prior one does not exist.
 176 IndexSet *PhaseLive::getset( Block *p ) {
 177   IndexSet *delta = _deltas[p->_pre_order-1];
 178   if( !delta )                  // Not on worklist?
 179     // Get a free set; flag as being on worklist
 180     delta = _deltas[p->_pre_order-1] = getfreeset();
 181   return delta;                 // Return set of new live-out items
 182 }
 183 
 184 // Pull from free list, or allocate.  Internal allocation on the returned set
 185 // is always from thread local storage.
 186 IndexSet *PhaseLive::getfreeset( ) {
 187   IndexSet *f = _free_IndexSet;
 188   if( !f ) {
 189     f = new IndexSet;
 190 //    f->set_arena(Thread::current()->resource_area());
 191     f->initialize(_maxlrg, Thread::current()->resource_area());
 192   } else {
 193     // Pull from free list
 194     _free_IndexSet = f->next();
 195   //f->_cnt = 0;                        // Reset to empty
 196 //    f->set_arena(Thread::current()->resource_area());
 197     f->initialize(_maxlrg, Thread::current()->resource_area());
 198   }
 199   return f;
 200 }
 201 
 202 // Free an IndexSet from a block.
 203 void PhaseLive::freeset( const Block *p ) {
 204   IndexSet *f = _deltas[p->_pre_order-1];
 205   f->set_next(_free_IndexSet);
 206   _free_IndexSet = f;           // Drop onto free list
 207   _deltas[p->_pre_order-1] = NULL;
 208 }
 209 
 210 // Add a live-out value to a given blocks live-out set.  If it is new, then
 211 // also add it to the delta set and stick the block on the worklist.
 212 void PhaseLive::add_liveout( Block *p, uint r, VectorSet &first_pass ) {
 213   IndexSet *live = &_live[p->_pre_order-1];
 214   if( live->insert(r) ) {       // If actually inserted...
 215     // We extended the live-out set.  See if the value is generated locally.
 216     // If it is not, then we must extend the live-in set.
 217     if( !_defs[p->_pre_order-1].member( r ) ) {


 221       getset(p)->insert(r);
 222     }
 223   }
 224 }
 225 
 226 // Add a vector of live-out values to a given blocks live-out set.
 227 void PhaseLive::add_liveout( Block *p, IndexSet *lo, VectorSet &first_pass ) {
 228   IndexSet *live = &_live[p->_pre_order-1];
 229   IndexSet *defs = &_defs[p->_pre_order-1];
 230   IndexSet *on_worklist = _deltas[p->_pre_order-1];
 231   IndexSet *delta = on_worklist ? on_worklist : getfreeset();
 232 
 233   IndexSetIterator elements(lo);
 234   uint r;
 235   while ((r = elements.next()) != 0) {
 236     if( live->insert(r) &&      // If actually inserted...
 237         !defs->member( r ) )    // and not defined locally
 238       delta->insert(r);         // Then add to live-in set
 239   }
 240 
 241   if( delta->count() ) {                // If actually added things
 242     _deltas[p->_pre_order-1] = delta; // Flag as on worklist now
 243     if( !on_worklist &&         // Not on worklist?
 244         first_pass.test(p->_pre_order) )
 245       _worklist->push(p);       // Actually go on worklist if already 1st pass
 246   } else {                      // Nothing there; just free it
 247     delta->set_next(_free_IndexSet);
 248     _free_IndexSet = delta;     // Drop onto free list
 249   }
 250 }
 251 
 252 #ifndef PRODUCT
 253 // Dump the live-out set for a block
 254 void PhaseLive::dump( const Block *b ) const {
 255   tty->print("Block %d: ",b->_pre_order);
 256   tty->print("LiveOut: ");  _live[b->_pre_order-1].dump();
 257   uint cnt = b->number_of_nodes();
 258   for( uint i=0; i<cnt; i++ ) {
 259     tty->print("L%d/", _names.at(b->get_node(i)->_idx));
 260     b->get_node(i)->dump();
 261   }




 117       use->remove(r);
 118     }
 119 
 120     // Push these live-in things to predecessors
 121     for (uint l = 1; l < block->num_preds(); l++) {
 122       Block* p = _cfg.get_block_for_node(block->pred(l));
 123       add_liveout(p, use, first_pass);
 124 
 125       // PhiNode uses go in the live-out set of prior blocks.
 126       for (uint k = i; k > 0; k--) {
 127         add_liveout(p, _names.at(block->get_node(k-1)->in(l)->_idx), first_pass);
 128       }
 129     }
 130     freeset(block);
 131     first_pass.set(block->_pre_order);
 132 
 133     // Inner loop: blocks that picked up new live-out values to be propagated
 134     while (_worklist->size()) {
 135       Block* block = _worklist->pop();
 136       IndexSet *delta = getset(block);
 137       assert( !delta->is_empty(), "missing delta set" );
 138 
 139       // Add new-live-in to predecessors live-out sets
 140       for (uint l = 1; l < block->num_preds(); l++) {
 141         Block* predecessor = _cfg.get_block_for_node(block->pred(l));
 142         add_liveout(predecessor, delta, first_pass);
 143       }
 144 
 145       freeset(block);
 146     } // End of while-worklist-not-empty
 147 
 148   } // End of for-all-blocks-outer-loop
 149 
 150   // We explicitly clear all of the IndexSets which we are about to release.
 151   // This allows us to recycle their internal memory into IndexSet's free list.
 152 
 153   for (i = 0; i < _cfg.number_of_blocks(); i++) {
 154     _defs[i].clear();
 155     if (_deltas[i]) {
 156       // Is this always true?
 157       _deltas[i]->clear();


 170 void PhaseLive::stats(uint iters) const {
 171 }
 172 #endif
 173 
 174 // Get an IndexSet for a block.  Return existing one, if any.  Make a new
 175 // empty one if a prior one does not exist.
 176 IndexSet *PhaseLive::getset( Block *p ) {
 177   IndexSet *delta = _deltas[p->_pre_order-1];
 178   if( !delta )                  // Not on worklist?
 179     // Get a free set; flag as being on worklist
 180     delta = _deltas[p->_pre_order-1] = getfreeset();
 181   return delta;                 // Return set of new live-out items
 182 }
 183 
 184 // Pull from free list, or allocate.  Internal allocation on the returned set
 185 // is always from thread local storage.
 186 IndexSet *PhaseLive::getfreeset( ) {
 187   IndexSet *f = _free_IndexSet;
 188   if( !f ) {
 189     f = new IndexSet;
 190     f->initialize(_maxlrg);

 191   } else {
 192     // Pull from free list
 193     _free_IndexSet = f->next();
 194     f->initialize(_maxlrg);


 195   }
 196   return f;
 197 }
 198 
 199 // Free an IndexSet from a block.
 200 void PhaseLive::freeset( const Block *p ) {
 201   IndexSet *f = _deltas[p->_pre_order-1];
 202   f->set_next(_free_IndexSet);
 203   _free_IndexSet = f;           // Drop onto free list
 204   _deltas[p->_pre_order-1] = NULL;
 205 }
 206 
 207 // Add a live-out value to a given blocks live-out set.  If it is new, then
 208 // also add it to the delta set and stick the block on the worklist.
 209 void PhaseLive::add_liveout( Block *p, uint r, VectorSet &first_pass ) {
 210   IndexSet *live = &_live[p->_pre_order-1];
 211   if( live->insert(r) ) {       // If actually inserted...
 212     // We extended the live-out set.  See if the value is generated locally.
 213     // If it is not, then we must extend the live-in set.
 214     if( !_defs[p->_pre_order-1].member( r ) ) {


 218       getset(p)->insert(r);
 219     }
 220   }
 221 }
 222 
 223 // Add a vector of live-out values to a given blocks live-out set.
 224 void PhaseLive::add_liveout( Block *p, IndexSet *lo, VectorSet &first_pass ) {
 225   IndexSet *live = &_live[p->_pre_order-1];
 226   IndexSet *defs = &_defs[p->_pre_order-1];
 227   IndexSet *on_worklist = _deltas[p->_pre_order-1];
 228   IndexSet *delta = on_worklist ? on_worklist : getfreeset();
 229 
 230   IndexSetIterator elements(lo);
 231   uint r;
 232   while ((r = elements.next()) != 0) {
 233     if( live->insert(r) &&      // If actually inserted...
 234         !defs->member( r ) )    // and not defined locally
 235       delta->insert(r);         // Then add to live-in set
 236   }
 237 
 238   if( !delta->is_empty() ) {                // If actually added things
 239     _deltas[p->_pre_order-1] = delta; // Flag as on worklist now
 240     if( !on_worklist &&         // Not on worklist?
 241         first_pass.test(p->_pre_order) )
 242       _worklist->push(p);       // Actually go on worklist if already 1st pass
 243   } else {                      // Nothing there; just free it
 244     delta->set_next(_free_IndexSet);
 245     _free_IndexSet = delta;     // Drop onto free list
 246   }
 247 }
 248 
 249 #ifndef PRODUCT
 250 // Dump the live-out set for a block
 251 void PhaseLive::dump( const Block *b ) const {
 252   tty->print("Block %d: ",b->_pre_order);
 253   tty->print("LiveOut: ");  _live[b->_pre_order-1].dump();
 254   uint cnt = b->number_of_nodes();
 255   for( uint i=0; i<cnt; i++ ) {
 256     tty->print("L%d/", _names.at(b->get_node(i)->_idx));
 257     b->get_node(i)->dump();
 258   }